Changhao Yi, Cunlu Zhou, and Jun Takahashi,

Quantum 8, 1579 (2024).

As a signal recovery algorithm, compressed sensing is particularly effective when the data has low complexity and samples are scarce, which aligns natually with the task of quantum phase est…

Brandon J. Furey, Zhenlin Wu, Mariano Isaza-Monsalve, Stefan Walser, Elyas Mattivi, René Nardi, and Philipp Schindler,

Quantum 8, 1578 (2024).

The rotation of trapped molecules offers a promising platform for quantum technologies and quantum information processing. In parallel, quantum error correction codes that can protect quantu…

Bálint Domokos, Áron Márton, and János K. Asbóth,

Quantum 8, 1577 (2024).

As current experiments already realize small quantum circuits on error corrected qubits, it is important to fully understand the effect of physical errors on the logical error channels of th…

Yoann Piétri, Matteo Schiavon, Valentina Marulanda Acosta, Baptiste Gouraud, Luis Trigo Vidarte, Philippe Grangier, Amine Rhouni, and Eleni Diamanti,

Quantum 8, 1575 (2024).

Quantum Key Distribution (QKD) enables secret key exchange between two remote parties with information-theoretic security rooted in the laws of quantum physics. Encoding key information in c…

Michele Masini, Marie Ioannou, Nicolas Brunner, Stefano Pironio, and Pavel Sekatski,

Quantum 8, 1574 (2024).

Photon loss represents a major challenge for the implementation of quantum communication protocols with untrusted devices, e.g. in the device-independent (DI) or semi-DI approaches. Determin…

Garazi Muguruza and Florian Speelman,

Quantum 8, 1573 (2024).

We introduce Port-Based State Preparation (PBSP), a teleportation task where Alice holds a complete classical description of the target state and Bob's correction operations are restricted t…

Seungbeom Chin, Marcin Karczewski, and Yong-Su Kim,

Quantum 8, 1572 (2024).

Non-destructive heralded entanglement with photons is a valuable resource for quantum information processing. However, they generally entail ancillary particles and modes that amplify the ci…

Qiushi Liu and Yuxiang Yang,

Quantum 8, 1571 (2024).

Optimized quantum control can enhance the performance and noise resilience of quantum metrology. However, the optimization quickly becomes intractable when multiple control operations are ap…

Wayne Lin, Georgios Piliouras, Ryann Sim, and Antonios Varvitsiotis,

Quantum 8, 1569 (2024).

As quantum processors advance, the emergence of large-scale decentralized systems involving interacting quantum-enabled agents is on the horizon. Recent research efforts have explored quantu…

Isaac Layton, Jonathan Oppenheim, and Zachary Weller-Davies,

Quantum 8, 1565 (2024).

We study the back-reaction of quantum systems onto classical ones. Taking the starting point that semi-classical physics should be described at all times by a point in classical phase space…

Jinzhao Wang and Shunyu Yao,

Quantum 8, 1564 (2024).

Quantum energy teleportation (QET) is the phenomenon in which locally inaccessible energy is activated as extractable work through collaborative local operations and classical communication…

Campbell McLauchlan, György P. Gehér, and Alexandra E. Moylett,

Quantum 8, 1562 (2024).

Floquet codes are an intriguing generalisation of stabiliser and subsystem codes, which can provide good fault-tolerant characteristics while benefiting from reduced connectivity requirement…

Matthias Christandl, Vladimir Lysikov, Vincent Steffan, Albert H. Werner, and Freek Witteveen,

Quantum 8, 1560 (2024).

Tensor networks provide succinct representations of quantum many-body states and are an important computational tool for strongly correlated quantum systems. Their expressive and computation…

Tianqi Chen and Tim Byrnes,

Quantum 8, 1557 (2024).

Quantum state preparation plays a crucial role in several areas of quantum information science, in applications such as quantum simulation, quantum metrology and quantum computing. However,…

Federico Belliardo, Fabio Zoratti, Florian Marquardt, and Vittorio Giovannetti,

Quantum 8, 1555 (2024).

Quantum sensors offer control flexibility during estimation by allowing manipulation by the experimenter across various parameters. For each sensing platform, pinpointing the optimal control…

Elisabeth Wybo and Martin Leib,

Quantum 8, 1554 (2024).

The parity mapping provides a geometrically local encoding of the Quantum Approximate Optimization Algorithm (QAOA), at the expense of having a quadratic qubit overhead for all-to-all connec…

David Jennings, Matteo Lostaglio, Robert B. Lowrie, Sam Pallister, and Andrew T. Sornborger,

Quantum 8, 1553 (2024).

How well can quantum computers simulate classical dynamical systems? There is increasing effort in developing quantum algorithms to efficiently simulate dynamics beyond Hamiltonian simulatio…

Harry Buhrman, Marten Folkertsma, Bruno Loff, and Niels M. P. Neumann,

Quantum 8, 1552 (2024).

Fault tolerant quantum computers repetitively apply a four-step procedure: First, perform a few one and two-qubit quantum gates. Second, perform a syndrome measurement on a subset of the qub…

Jérôme Denis, Jack Davis, Robert B. Mann, and John Martin,

Quantum 8, 1550 (2024).

Quasiprobability has become an increasingly popular notion for characterising non-classicality in quantum information, thermodynamics, and metrology. Two important distributions with non-pos…

Libor Caha, Xavier Coiteux-Roy, and Robert Koenig,

Quantum 8, 1548 (2024).

Gate-teleportation circuits are arguably among the most basic examples of computations believed to provide a quantum computational advantage: In seminal work [1], Terhal and DiVincenzo have…

Viktoria Kabel, Anne-Catherine de la Hamette, Esteban Castro-Ruiz, and Časlav Brukner,

Quantum 8, 1547 (2024).

Without a complete theory of quantum gravity, the question of how quantum fields and quantum particles behave in a superposition of spacetimes seems beyond the reach of theoretical and exper…

Joseph T. Iosue, T. C. Mooney, Adam Ehrenberg, and Alexey V. Gorshkov,

Quantum 8, 1546 (2024).

Toric $t$-designs, or equivalently $t$-designs on the diagonal subgroup of the unitary group, are sets of points on the torus over which sums reproduce integrals of degree $t$ monomials over the f…

Bernhard Jobst, Kevin Shen, Carlos A. Riofrío, Elvira Shishenina, and Frank Pollmann,

Quantum 8, 1544 (2024).

Machine learning tasks are an exciting application for quantum computers, as it has been proven that they can learn certain problems more efficiently than classical ones. Applying quantum ma…

Gavin S. Hartnett, Aaron Barbosa, Pranav S. Mundada, Michael Hush, Michael J. Biercuk, and Yuval Baum,

Quantum 8, 1542 (2024).

We introduce and experimentally test a machine-learning-based method for ranking logically equivalent quantum circuits based on expected performance estimates derived from a training procedu…

Takaya Matsuura, Shinichiro Yamano, Yui Kuramochi, Toshihiko Sasaki, and Masato Koashi,

Quantum 8, 1540 (2024).

We developed new concentration inequalities for a quantum state on an $N$-qudit system or measurement outcomes on it that apply to an adversarial setup, where an adversary prepares the quantum…

Florian Hopfmueller, Maxime Tremblay, Philippe St-Jean, Baptiste Royer, and Marc-Antoine Lemonde,

Quantum 8, 1539 (2024).

A promising route towards fault-tolerant quantum error correction is the concatenation of a Gottesman-Kitaev-Preskill (GKP) code with a qubit code. Development of such concatenated codes req…

Mark R. Hirsbrunner, Diana Chamaki, J. Wayne Mullinax, and Norm M. Tubman,

Quantum 8, 1538 (2024).

The unitary coupled cluster (UCC) ansatz is a promising tool for achieving high-precision results using the variational quantum eigensolver (VQE) algorithm in the NISQ era. However, results…

Alicja Dutkiewicz, Thomas E. O’Brien, and Thomas Schuster,

Quantum 8, 1537 (2024).

We study the problem of learning the Hamiltonian of a many-body quantum system from experimental data. We show that the rate of learning depends on the amount of control available during the…

Mordecai Waegell, Jeff Tollaksen, and Yakir Aharonov,

Quantum 8, 1536 (2024).

The Quantum Cheshire Cat experiment showed that when weak measurements are performed on pre- and post-selected system, the counterintuitive result has been obtained that a neutron is measure…

Franz G. Fuchs and Ruben Pariente Bassa,

Quantum 8, 1535 (2024).

We present a novel formalism to both understand and construct mixers that preserve a given subspace. The method connects and utilizes the stabilizer formalism that is used in error correctin…

D. Fernández-Fernández, Yue Ban, and G. Platero,

Quantum 8, 1533 (2024).

Quantum information transfer is fundamental for scalable quantum computing in any potential platform and architecture. Hole spin qubits, owing to their intrinsic spin-orbit interaction (SOI)…

Jesse Berwald, Nicholas Chancellor, and Raouf Dridi,

Quantum 8, 1532 (2024).

It has previously been established that adiabatic quantum computation, operating based on a continuous Zeno effect due to dynamical phases between eigenstates, is able to realise an optimal…

Rutuja Kshirsagar, Amara Katabarwa, and Peter D. Johnson,

Quantum 8, 1531 (2024).

The hope of the quantum computing field is that quantum architectures are able to scale up and realize fault-tolerant quantum computing. Due to engineering challenges, such “cheap'' error c…

Jonathan Allcock, Jinge Bao, Joao F. Doriguello, Alessandro Luongo, and Miklos Santha,

Quantum 8, 1530 (2024).

We explore the power of the unbounded Fan-Out gate and the Global Tunable gates generated by Ising-type Hamiltonians in constructing constant-depth quantum circuits, with particular attentio…

Suhail Ahmad Rather,

Quantum 8, 1528 (2024).

Dual unitary gates are highly non-local two-qudit unitary gates that have been studied extensively in quantum many-body physics and quantum information in the recent past. A special class of…

Eric R. Anschuetz, David Gamarnik, and Bobak Kiani,

Quantum 8, 1527 (2024).

In an important recent development, Anshu, Breuckmann, and Nirkhe [3] resolved positively the so-called No Low-Energy Trivial State (NLTS) conjecture by Freedman and Hastings. The conjecture…

Lexin Ding, Cheng-Lin Hong, and Christian Schilling,

Quantum 8, 1525 (2024).

The extension of the Rayleigh-Ritz variational principle to ensemble states $\rho_{\mathbf{w}}\equiv\sum_k w_k |\Psi_k\rangle \langle\Psi_k|$ with fixed weights $w_k$ lies ultimately at the hear…

Ge Bai, Dominik Šafránek, Joseph Schindler, Francesco Buscemi, and Valerio Scarani,

Quantum 8, 1524 (2024).

Observational entropy captures both the intrinsic uncertainty of a thermodynamic state and the lack of knowledge due to coarse-graining. We demonstrate two interpretations of observational e…

Alice Barthe and Adrián Pérez-Salinas,

Quantum 8, 1523 (2024).

Quantum re-uploading models have been extensively investigated as a form of machine learning within the context of variational quantum algorithms. Their trainability and expressivity are not…

Álvaro Gómez-León,

Quantum 8, 1522 (2024).

Floquet topological phases emerge when systems are periodically driven out-of-equilibrium. They gained attention due to their external control, which allows to simulate a wide variety of sta…

Yanic Cardin and Nicolás Quesada,

Quantum 8, 1521 (2024).

We develop closed-form expressions for the moments and cumulants of Gaussian states when measured in the photon-number basis. We express the photon-number moments of a Gaussian state in term…

Zohreh Davoudi, Chung-Chun Hsieh, and Saurabh V. Kadam,

Quantum 8, 1520 (2024).

Quantum simulation holds promise of enabling a complete description of high-energy scattering processes rooted in gauge theories of the Standard Model. A first step in such simulations is pr…

Ulysse Chabaud, Roohollah Ghobadi, Salman Beigi, and Saleh Rahimi-Keshari,

Quantum 8, 1519 (2024).

Quantum kernel methods are a proposal for achieving quantum computational advantage in machine learning. They are based on a hybrid classical-quantum computation where a function called the…

Johannes Fankhauser,

Quantum 8, 1518 (2024).

One of quantum theory's salient features is its apparent indeterminism, i.e. measurement outcomes are typically probabilistic. We formally define and address whether this uncertainty is unav…

Masahito Hayashi,

Quantum 8, 1517 (2024).

A Dicke state and its decohered state are invariant for permutation. However, when another qubits state to each of them is attached, the whole state is not invariant for permutation, and has…

Jwo-Sy Chen, Erik Nielsen, Matthew Ebert, Volkan Inlek, Kenneth Wright, Vandiver Chaplin, Andrii Maksymov, Eduardo Páez, Amrit Poudel, Peter Maunz, and John Gamble,

Quantum 8, 1516 (2024).

Quantum computers are rapidly becoming more capable, with dramatic increases in both qubit count [1] and quality [2]. Among different hardware approaches, trapped-ion quantum processors are…

Teiko Heinosaari and Oskari Kerppo,

Quantum 8, 1515 (2024).

A prepare-and-measure scenario is naturally described by a communication matrix that collects all conditional outcome probabilities of the scenario into a row-stochastic matrix. The set of a…

Hippolyte Dourdent, Alastair A. Abbott, Ivan Šupić, and Cyril Branciard,

Quantum 8, 1514 (2024).

Causal nonseparability is the property underlying quantum processes incompatible with a definite causal order. So far it has remained a central open question as to whether any process with a…

Matteo Votto, Johannes Zeiher, and Benoît Vermersch,

Quantum 8, 1513 (2024).

We propose a protocol to realize quantum simulation and computation in spin systems with long-range interactions. Our approach relies on the local addressing of single spins with external fi…

Alex Fischer and Akimasa Miyake,

Quantum 8, 1511 (2024).

Real quantum computers will be subject to complicated, qubit-dependent noise, instead of simple noise such as depolarizing noise with the same strength for all qubits. We can do quantum erro…

David Raveh and Rafael I. Nepomechie,

Quantum 8, 1510 (2024).

We present an explicit quantum circuit that prepares an arbitrary $U(1)$-eigenstate on a quantum computer, including the exact eigenstates of the spin-$1/2 XXZ$ quantum spin chain with either op…

Dylan Lewis, Stephan Eidenbenz, Balasubramanya Nadiga, and Yiğit Subaşı,

Quantum 8, 1509 (2024).

We investigate the limitations of quantum computers for solving nonlinear dynamical systems. In particular, we tighten the worst-case bounds of the quantum Carleman linearisation (QCL) algor…

Pablo Arrighi, Amélia Durbec, and Matt Wilson,

Quantum 8, 1508 (2024).

The formalism of quantum theory over discrete systems is extended in two significant ways. First, quantum evolutions are generalized to act over entire network configurations, so that nodes…

Lucas Berent, Lukas Burgholzer, Peter-Jan H.S. Derks, Jens Eisert, and Robert Wille,

Quantum 8, 1506 (2024).

In classical computing, error-correcting codes are well established and are ubiquitous both in theory and practical applications. For quantum computing, error-correction is essential as well…

Anne Matthies, Mark Rudner, Achim Rosch, and Erez Berg,

Quantum 8, 1505 (2024).

We propose a simple, robust protocol to prepare a low-energy state of an arbitrary Hamiltonian on a quantum computer or programmable quantum simulator. The protocol is inspired by the adiaba…

M. Emre Sahin, Benjamin C. B. Symons, Pushpak Pati, Fayyaz Minhas, Declan Millar, Maria Gabrani, Stefano Mensa, and Jan Lukas Robertus,

Quantum 8, 1502 (2024).

Quantum machine learning with quantum kernels for classification problems is a growing area of research. Recently, quantum kernel alignment techniques that parameterise the kernel have been…

Xiang Li, Hanxiang Shen, Weiguo Gao, and Yingzhou Li,

Quantum 8, 1500 (2024).

Nonlinear boolean equation systems play an important role in a wide range of applications. Grover's algorithm is one of the best-known quantum search algorithms in solving the nonlinear bool…

Antonio deMarti iOlius, Patricio Fuentes, Román Orús, Pedro M. Crespo, and Josu Etxezarreta Martinez,

Quantum 8, 1498 (2024).

Quantum technologies have the potential to solve certain computationally hard problems with polynomial or super-polynomial speedups when compared to classical methods. Unfortunately, the uns…

Zhao Zhang and Israel Klich,

Quantum 8, 1497 (2024).

While volume violation of area law has been exhibited in several quantum spin chains, the construction of a corresponding ground state in higher dimensions, entangled in more than one direct…

Shantanav Chakraborty,

Quantum 8, 1496 (2024).

We develop three new methods to implement any Linear Combination of Unitaries (LCU), a powerful quantum algorithmic tool with diverse applications. While the standard LCU procedure requires…

Akram Touil, Fabio Anza, Sebastian Deffner, and James P. Crutchfield,

Quantum 8, 1494 (2024).

Quantum Darwinism builds on decoherence theory to explain the emergence of classical behavior in a fundamentally quantum universe. Within this framework we prove two crucial insights about t…

Quanlong Wang, Richie Yeung, and Mark Koch,

Quantum 8, 1491 (2024).

ZX-calculus has proved to be a useful tool for quantum technology with a wide range of successful applications. Most of these applications are of an algebraic nature. However, other tasks th…

Nicola Pranzini, Guillermo García-Pérez, Esko Keski-Vakkuri, and Sabrina Maniscalco,

Quantum 8, 1490 (2024).

The Born rule describes the probability of obtaining an outcome when measuring an observable of a quantum system. As it can only be tested by measuring many copies of the system under consid…

Mathias B. M. Svendsen, Marcel Cech, Max Schemmer, and Beatriz Olmos,

Quantum 8, 1488 (2024).

We establish the concept of topological pumping in one-dimensional systems with long-range couplings and apply it to the transport of a photon in quantum optical systems. In our theoretical…

Zhiyan Ding, Haoya Li, Lin Lin, HongKang Ni, Lexing Ying, and Ruizhe Zhang,

Quantum 8, 1487 (2024).

Quantum phase estimation is one of the most powerful quantum primitives. This work proposes a new approach for the problem of multiple eigenvalue estimation: Quantum Multiple Eigenvalue Gaus…

Joshua Eglinton, Federico Carollo, Igor Lesanovsky, and Kay Brandner,

Quantum 8, 1486 (2024).

Microscopic thermal machines promise to play an important role in future quantum technologies. Making such devices widely applicable will require effective strategies to channel their output…

Yìlè Yīng, Marina Maciel Ansanelli, Andrea Di Biagio, Elie Wolfe, David Schmid, and Eric Gama Cavalcanti,

Quantum 8, 1485 (2024).

Nonclassical causal modeling was developed in order to explain violations of Bell inequalities while adhering to relativistic causal structure and $faithfulness$—that is, avoiding fine-tuned…

Alistair Letcher, Stefan Woerner, and Christa Zoufal,

Quantum 8, 1484 (2024).

The training of a parameterized model largely depends on the landscape of the underlying loss function. In particular, vanishing gradients are a central bottleneck in the scalability of vari…

Tan Van Vu, Tomotaka Kuwahara, and Keiji Saito,

Quantum 8, 1483 (2024).

Understanding the ultimate rate at which information propagates is a pivotal issue in nonequilibrium physics. Nevertheless, the task of elucidating the propagation speed inherent in quantum…

Aviv Aroch, Ronnie Kosloff, and Shimshon Kallush,

Quantum 8, 1482 (2024).

All quantum systems are subject to noise from the environment or external controls. This noise is a major obstacle to the realization of quantum technology. For example, noise limits the fid…

M. A. Rodríguez-García and F. E. Becerra,

Quantum 8, 1480 (2024).

Phase estimation plays a central role in communications, sensing, and information processing. Quantum correlated states, such as squeezed states, enable phase estimation beyond the shot-nois…

Benoit Seron, Leonardo Novo, Alex Arkhipov, and Nicolas J. Cerf,

Quantum 8, 1479 (2024).

In order to substantiate claims of quantum computational advantage, it is crucial to develop efficient methods for validating the experimental data. We propose a test of the correct function…

Anthony J. Brady, Jing Wu, and Quntao Zhuang,

Quantum 8, 1478 (2024).

Recent advancements in multi-mode Gottesman-Kitaev-Preskill (GKP) codes have shown great promise in enhancing the protection of both discrete and analog quantum information. This broadened r…

André Roque, Diogo Cruz, Francisco A. Monteiro, and Bruno C. Coutinho,

Quantum 8, 1476 (2024).

In this paper, we propose a novel bipartite entanglement purification protocol built upon hashing and upon the guessing random additive noise decoding (GRAND) approach recently devised for c…

Dawid A. Hryniuk and Marzena H. Szymańska,

Quantum 8, 1475 (2024).

We introduce a novel method of efficiently simulating the non-equilibrium steady state of large many-body open quantum systems with highly non-local interactions, based on a variational Mont…

Kazuki Sakamoto, Hayata Morisaki, Junichi Haruna, Etsuko Itou, Keisuke Fujii, and Kosuke Mitarai,

Quantum 8, 1474 (2024).

The Schwinger model is one of the simplest gauge theories. It is known that a topological term of the model leads to the infamous sign problem in the classical Monte Carlo method. In contras…

Stefano Baiguera, Shira Chapman, Giuseppe Policastro, and Tal Schwartzman,

Quantum 8, 1472 (2024).

Nielsen's approach to quantum state complexity relates the minimal number of quantum gates required to prepare a state to the length of geodesics computed with a certain norm on the manifold…

Xinyi Chen, Elad Hazan, Tongyang Li, Zhou Lu, Xinzhao Wang, and Rui Yang,

Quantum 8, 1471 (2024).

The problem of efficient quantum state learning, also called shadow tomography, aims to comprehend an unknown $d$-dimensional quantum state through POVMs. Yet, these states are rarely static;…

Benjamin D. M. Jones, Noah Linden, and Paul Skrzypczyk,

Quantum 8, 1470 (2024).

We consider models of quantum computation that involve operations performed on some fixed resourceful quantum state. Examples that fit this paradigm include magic state injection and measure…

Monica Conte, Vinicius Zampronio, Malte Röntgen, and Cristiane Morais Smith,

Quantum 8, 1469 (2024).

Here, we investigate the fractal-lattice Hubbard model using various numerical methods: exact diagonalization, the self-consistent diagonalization of a (mean-field) Hartree-Fock Hamiltonian…

Yinzi Xiao, Basudha Srivastava, and Mats Granath,

Quantum 8, 1468 (2024).

The code-capacity threshold of a scalable quantum error correcting stabilizer code can be expressed as a thermodynamic phase transition of a corresponding random-bond Ising model. Here we st…

Tian-Gang Zhou and Pengfei Zhang,

Quantum 8, 1467 (2024).

Classical shadow tomography serves as a potent tool for extracting numerous properties from quantum many-body systems with minimal measurements. Nevertheless, prevailing methods yielding opt…

A. Parra-Rodriguez and I. L. Egusquiza,

Quantum 8, 1466 (2024).

In lumped-element electrical circuit theory, the problem of solving Maxwell's equations in the presence of media is reduced to two sets of equations, the constitutive equations encapsulating…

Sadman Shanto, Andre Kuo, Clark Miyamoto, Haimeng Zhang, Vivek Maurya, Evangelos Vlachos, Malida Hecht, Chung Wa Shum, and Eli Levenson-Falk,

Quantum 8, 1465 (2024).

We present an open-source database of superconducting quantum device designs that may be used as the starting point for customized devices. Each design can be generated programmatically usin…

Jacopo Surace,

Quantum 8, 1464 (2024).

What would be the consequences if there were fundamental limits to our ability to experimentally explore the world? In this work we seriously consider this question. We assume the existence…

Kaito Wada, Kazuma Fukuchi, and Naoki Yamamoto,

Quantum 8, 1463 (2024).

Quantum-enhanced (i.e., higher performance by quantum effects than any classical methods) mean value estimation of observables is a fundamental task in various quantum technologies; in parti…

Brian J. J. Khor, D. M. Kürkçüoglu, T. J. Hobbs, G. N. Perdue, and Israel Klich,

Quantum 8, 1462 (2024).

In this work, we explore the interplay of confinement, string breaking and entanglement asymmetry on a 1D quantum Ising chain. We consider the evolution of an initial domain wall and show th…

Hiroki Hamaguchi, Kou Hamada, and Nobuyuki Yoshioka,

Quantum 8, 1461 (2024).

Nonstabilizerness, or magic, is an essential quantum resource for performing universal quantum computation. Specifically, Robustness of Magic (RoM) characterizes the usefulness of a given qu…

Marco Ballarin, Giovanni Cataldi, Giuseppe Magnifico, Daniel Jaschke, Marco Di Liberto, Ilaria Siloi, Simone Montangero, and Pietro Silvi,

Quantum 8, 1460 (2024).

We numerically analyze the feasibility of a platform-neutral, general strategy to perform quantum simulations of fermionic lattice field theories under open boundary conditions. The digital…

Michał Piotrak, Marek Kopciuch, Arash Dezhang Fard, Magdalena Smolis, Szymon Pustelny, and Kamil Korzekwa,

Quantum 8, 1459 (2024).

In this paper we introduce and investigate the concept of a $\textit{perfect quantum protractor}$, a pure quantum state $|\psi\rangle\in\mathcal{H}$ that generates three different orthogonal bas…

Bethany Davies, Álvaro G. Iñesta, and Stephanie Wehner,

Quantum 8, 1458 (2024).

Quantum networks crucially rely on the availability of high-quality entangled pairs of qubits, known as entangled links, distributed across distant nodes. Maintaining the quality of these li…

William Kirby,

Quantum 8, 1457 (2024).

This work provides a nonasymptotic error analysis of quantum Krylov algorithms based on real-time evolutions, subject to generic errors in the outputs of the quantum circuits. We prove upper…

Naga Dileep Varikuti and Soumik Bandyopadhyay,

Quantum 8, 1456 (2024).

Quantum state designs, by enabling an efficient sampling of random quantum states, play a quintessential role in devising and benchmarking various quantum protocols with broad applications r…

Zhihui Zhu, Joseph M. Lukens, and Brian T. Kirby,

Quantum 8, 1455 (2024).

Classical shadows (CS) offer a resource-efficient means to estimate quantum observables, circumventing the need for exhaustive state tomography. Here, we clarify and explore the connection b…

C. Gonzalez-Ballestero,

Quantum 8, 1454 (2024).

Most quantum theorists are familiar with different ways of describing the effective quantum dynamics of a system coupled to external degrees of freedom, such as the Born-Markov master equati…

Jie Lin, Benjamin MacLellan, Sobhan Ghanbari, Julie Belleville, Khuong Tran, Luc Robichaud, Roger G. Melko, Hoi-Kwong Lo, and Piotr Roztocki,

Quantum 8, 1453 (2024).

$\tt{GraphiQ}$ is a versatile open-source framework for designing photonic graph state generation schemes, with a particular emphasis on photon-emitter hybrid circuits. Built in Python, Graphi…

Santiago Llorens, Gael Sentís, and Ramon Muñoz-Tapia,

Quantum 8, 1452 (2024).

A source assumed to prepare a specified reference state sometimes prepares an anomalous one. We address the task of identifying these anomalous states in a series of $n$ preparations with $k$ an…

Nicholas Connolly, Vivien Londe, Anthony Leverrier, and Nicolas Delfosse,

Quantum 8, 1450 (2024).

We propose a decoder for the correction of erasures with hypergraph product codes, which form one of the most popular families of quantum LDPC codes. Our numerical simulations show that this…

Davide Lonigro, Fattah Sakuldee, Łukasz Cywiński, Dariusz Chruściński, and Piotr Szańkowski,

Quantum 8, 1447 (2024).

The multitime probability distributions obtained by repeatedly probing a quantum system via the measurement of an observable generally violate Kolmogorov's consistency property. Therefore, o…

Aleksandrs Belovs, Stacey Jeffery, and Duyal Yolcu,

Quantum 8, 1444 (2024).

Quantum query complexity has several nice properties with respect to composition. First, bounded-error quantum query algorithms can be composed without incurring log factors through error re…

Carolina Moreira Ferrera, Robin Simmons, James Purcell, Daniel Collins, and Sandu Popescu,

Quantum 8, 1443 (2024).

Here we introduce the concept of classical input – quantum output (C-Q) non-signalling boxes, a generalisation of the classical input – classical output (C-C) non-signalling boxes. We argue…

Pontus Vikstål, Giulia Ferrini, and Shruti Puri,

Quantum 8, 1441 (2024).

Virtual distillation has been proposed as an error mitigation protocol for estimating the expectation values of observables in quantum algorithms. It proceeds by creating a cyclic permutatio…

Luca Apadula, Esteban Castro-Ruiz, and Časlav Brukner,

Quantum 8, 1440 (2024).

Since their first introduction, Quantum Reference Frame (QRF) transformations have been extensively discussed, generalising the covariance of physical laws to the quantum domain. Despite imp…

Gregory Bentsen, Phuc Nguyen, and Brian Swingle,

Quantum 8, 1439 (2024).

We discuss families of approximate quantum error correcting codes which arise as the nearly-degenerate ground states of certain quantum many-body Hamiltonians composed of non-commuting terms…

Zongkang Zhang, Anbang Wang, Xiaosi Xu, and Ying Li,

Quantum 8, 1438 (2024).

The Krylov subspace methods, being one category of the most important classical numerical methods for linear algebra problems, can be much more powerful when generalised to quantum computing…

Santiago Rojas-Rojas, Daniel Martínez, Kei Sawada, Luciano Pereira, Stephen P. Walborn, Esteban S. Gómez, Nadja K. Bernardes, and Gustavo Lima,

Quantum 8, 1436 (2024).

With the advent of quantum technology, the interest in communication tasks assisted by quantum systems has increased both in academia and industry. Nonetheless, the transmission of a quantum…

Michael A. Rampp and Pieter W. Claeys,

Quantum 8, 1434 (2024).

The Hayden-Preskill protocol probes the capability of information recovery from local subsystems after unitary dynamics. As such it resolves the capability of quantum many-body systems to dy…

Matteo Rosati,

Quantum 8, 1433 (2024).

We consider the tasks of learning quantum states, measurements and channels generated by continuous-variable (CV) quantum circuits. This family of circuits is suited to describe optical quan…

Andrew M. Projansky, Joshuah T. Heath, and James D. Whitfield,

Quantum 8, 1432 (2024).

The entanglement level statistics of a quantum state have recently been proposed to be a signature of universality in the underlying quantum circuit. This is a consequence of level repulsion…

Stanisław Kurzyna, Bartosz Niewelt, Mateusz Mazelanik, Wojciech Wasilewski, and Michał Parniak,

Quantum 8, 1431 (2024).

Collective Rydberg excitations provide promising applications ranging from quantum information processing, and quantum computing to ultra-sensitive electrometry. However, their short lifetim…

Iosifina Angelidi, Marcin Szyniszewski, and Arijeet Pal,

Quantum 8, 1430 (2024).

Long-range entangled states are vital for quantum information processing and quantum metrology. Preparing such states by combining measurements with unitary gates opened new possibilities fo…

Emma C. King, Luigi Giannelli, Raphaël Menu, Johannes N. Kriel, and Giovanna Morigi,

Quantum 8, 1428 (2024).

We analyze the efficiency of protocols for adiabatic quantum state transfer assisted by an engineered reservoir. The target dynamics is a quantum trajectory in the Hilbert space and is a fix…

Jasmine Sinanan-Singh, Gabriel L. Mintzer, Isaac L. Chuang, and Yuan Liu,

Quantum 8, 1427 (2024).

Quantum systems of infinite dimension, such as bosonic oscillators, provide vast resources for quantum sensing. Yet, a general theory on how to manipulate such bosonic modes for sensing beyo…

Abhijith Jayakumar, Stefano Chessa, Carleton Coffrin, Andrey Y. Lokhov, Marc Vuffray, and Sidhant Misra,

Quantum 8, 1426 (2024).

We present a general denoising algorithm for performing $\textit{simultaneous tomography}$ of quantum states and measurement noise. This algorithm allows us to fully characterize state prepara…

Alejandro Pozas-Kerstjens, Senaida Hernández-Santana, José Ramón Pareja Monturiol, Marco Castrillón López, Giannicola Scarpa, Carlos E. González-Guillén, and David Pérez-García,

Quantum 8, 1425 (2024).

Tensor networks, widely used for providing efficient representations of low-energy states of local quantum many-body systems, have been recently proposed as machine learning architectures wh…

Grégoire de Gliniasty, Paul Hilaire, Pierre-Emmanuel Emeriau, Stephen C. Wein, Alexia Salavrakos, and Shane Mansfield,

Quantum 8, 1423 (2024).

We introduce an adaptable and modular hybrid architecture designed for fault-tolerant quantum computing. It combines quantum emitters and linear-optical entangling gates to leverage the stre…

Zheng An, Chenfeng Cao, Cheng-Qian Xu, and D. L. Zhou,

Quantum 8, 1421 (2024).

Identifying phases of matter presents considerable challenges, particularly within the domain of quantum theory, where the complexity of ground states appears to increase exponentially with…

Dimiter Ostrev, Davide Orsucci, Francisco Lázaro, and Balazs Matuz,

Quantum 8, 1420 (2024).

Several notions of code products are known in quantum error correction, such as hypergraph products, homological products, lifted products, balanced products, to name a few. In this paper we…

Shubhayan Sarkar,

Quantum 8, 1419 (2024).

Quantum networks with multiple sources allow the observation of quantum nonlocality without inputs. Consequently, the incompatibility of measurements is not a necessity for observing quantum…

Stefan Bäuml, Carlos Pascual-García, Victoria Wright, Omar Fawzi, and Antonio Acín,

Quantum 8, 1418 (2024).

Continuous variable quantum key distribution with discrete modulation has the potential to provide information-theoretic security using widely available optical elements and existing telecom…

Naeimeh Mohseni, Junheng Shi, Tim Byrnes, and Michael J. Hartmann,

Quantum 8, 1417 (2024).

Machine learning has shown significant breakthroughs in quantum science, where in particular deep neural networks exhibited remarkable power in modeling quantum many-body systems. Here, we e…

Rahul Sarkar and Theodore J. Yoder,

Quantum 8, 1416 (2024).

Twist defects in surface codes can be used to encode more logical qubits, improve the code rate, and implement logical gates. In this work we provide a rigorous formalism for constructing su…

Simon Milz and Marco Túlio Quintino,

Quantum 8, 1415 (2024).

Many fundamental and key objects in quantum mechanics are linear mappings between particular affine/linear spaces. This structure includes basic quantum elements such as states, measurements…

Sara Ditsch and Tobias Haas,

Quantum 8, 1414 (2024).

We present a general way of quantifying the entropic uncertainty of quantum field configurations in phase space in terms of entropic distinguishability with respect to the vacuum. Our approa…

Kyusung Hwang,

Quantum 8, 1412 (2024).

Quantum spin liquids and anyons, used to be subjects of condensed matter physics, now are realized in various platforms of qubits, offering unprecedented opportunities to investigate fundame…

Pablo Viñas Martínez, Esperanza López, and Alejandro Bermudez,

Quantum 8, 1411 (2024).

The quantum simulation of magnetism in trapped-ion systems makes use of the crystal vibrations to mediate pairwise interactions between spins, which are encoded in the internal electronic st…

Weiyuan Gong, Shuo Zhou, and Tongyang Li,

Quantum 8, 1409 (2024).

Digital quantum simulation has broad applications in approximating unitary evolution of Hamiltonians. In practice, many simulation tasks for quantum systems focus on quantum states in the lo…

Jovan Jovanović, Carolin Wille, Daan Timmers, and Steven H. Simon,

Quantum 8, 1408 (2024).

In this work we present a proposal for realising non-Abelian anyons on a NISQ device. In particular we explore the feasibility of implementing the quantum double model $D(D_4)$. We propose tec…

Ke Wang and Xiantao Li,

Quantum 8, 1407 (2024).

Models for open quantum systems, which play important roles in electron transport problems and quantum computing, must take into account the interaction of the quantum system with the surrou…

J. Escandón-Monardes, D. Uzcátegui, M. Rivera-Tapia, S. P. Walborn, and A. Delgado,

Quantum 8, 1405 (2024).

We propose an estimation procedure for $d$-dimensional unitary transformations. For $d\gt2$, the unitary transformations close to the identity are estimated saturating the quantum Cramér-Rao bou…

Fereshte Shahbeigi, Christopher T. Chubb, Ryszard Kukulski, Łukasz Pawela, and Kamil Korzekwa,

Quantum 8, 1404 (2024).

The classical embeddability problem asks whether a given stochastic matrix $T$, describing transition probabilities of a $d$-level system, can arise from the underlying homogeneous continuous-ti…

Pierre Botteron, Anne Broadbent, Reda Chhaibi, Ion Nechita, and Clément Pellegrini,

Quantum 8, 1402 (2024).

Communication complexity quantifies how difficult it is for two distant computers to evaluate a function $f(X,Y)$, where the strings $X$ and $Y$ are distributed to the first and second computer re…

Kshiti Sneh Rai, J. Ignacio Cirac, and Álvaro M. Alhambra,

Quantum 8, 1401 (2024).

We show how to efficiently simulate pure quantum states in one dimensional systems that have both finite energy density and vanishingly small energy fluctuations. We do so by studying the pe…

Campbell McLauchlan and Benjamin Béri,

Quantum 8, 1400 (2024).

Majorana zero modes (MZMs) are promising candidates for topologically-protected quantum computing hardware, however their large-scale use will likely require quantum error correction. Majora…

Yusuf Alnawakhtha, Atul Mantri, Carl A. Miller, and Daochen Wang,

Quantum 8, 1399 (2024).

Trapdoor claw-free functions (TCFs) are immensely valuable in cryptographic interactions between a classical client and a quantum server. Typically, a protocol has the quantum server prepare…

Jonathan Conrad, Jens Eisert, and Jean-Pierre Seifert,

Quantum 8, 1398 (2024).

We introduce a new class of random Gottesman-Kitaev-Preskill (GKP) codes derived from the cryptanalysis of the so-called NTRU cryptosystem. The derived codes are $good$ in that they exhibit co…

Gabriel Wong, Robert Raussendorf, and Bartlomiej Czech,

Quantum 8, 1397 (2024).

Measurement-Based Quantum Computation (MBQC) is a model of quantum computation, which uses local measurements instead of unitary gates. Here we explain that the MBQC procedure has a fundamen…

L. Sunil Chandran and Rishikesh Gajjala,

Quantum 8, 1396 (2024).

The most efficient automated way to construct a large class of quantum photonic experiments is via abstract representation of graphs with certain properties. While new directions were explor…

Lorenzo Leone, Salvatore F.E. Oliviero, Lukasz Cincio, and M. Cerezo,

Quantum 8, 1395 (2024).

Variational Quantum Algorithms (VQAs) and Quantum Machine Learning (QML) models train a parametrized quantum circuit to solve a given learning task. The success of these algorithms greatly h…

György P. Gehér, Campbell McLauchlan, Earl T. Campbell, Alexandra E. Moylett, and Ophelia Crawford,

Quantum 8, 1394 (2024).

We simulate the logical Hadamard gate in the surface code under a circuit-level noise model, compiling it to a physical circuit on square-grid connectivity hardware. Our paper is the first t…

Andreu Riera-Campeny, Marc Roda-Llordes, Piotr T. Grochowski, and Oriol Romero-Isart,

Quantum 8, 1393 (2024).

We derive an analytical expression of a Wigner function that approximately describes the time evolution of the one-dimensional motion of a particle in a nonharmonic potential. Our method inv…

Subhajit Sarkar and Berislav Buča,

Quantum 8, 1392 (2024).

Semiconductor platforms are emerging as a promising architecture for storing and processing quantum information, e.g., in quantum dot spin qubits. However, charge noise coming from interacti…

Piotr Szańkowski and Łukasz Cywiński,

Quantum 8, 1390 (2024).

We investigate what can be concluded about a quantum system when sequential quantum measurements of its observable – a prominent example of the so-called quantum stochastic process – fulfill…

Reinis Irmejs, Mari Carmen Bañuls, and J. Ignacio Cirac,

Quantum 8, 1389 (2024).

We introduce a quantum algorithm to efficiently prepare states with a small energy variance at the target energy. We achieve it by filtering a product state at the given energy with a Lorent…

Tizian Blatz, Joyce Kwan, Julian Léonard, and Annabelle Bohrdt,

Quantum 8, 1388 (2024).

New generations of ultracold-atom experiments are continually raising the demand for efficient solutions to optimal control problems. Here, we apply Bayesian optimization to improve a state-…

Artur Slobodeniuk, Tomáš Novotný, and Radim Filip,

Quantum 8, 1386 (2024).

Quantum coherence is a crucial prerequisite for quantum technologies. Therefore, the robust generation, as autonomous as possible, of quantum coherence remains the essential problem for deve…

David A. Kreplin and Marco Roth,

Quantum 8, 1385 (2024).

Quantum neural networks (QNNs) use parameterized quantum circuits with data-dependent inputs and generate outputs through the evaluation of expectation values. Calculating these expectation…

Sebastian P. Kish, Patrick J. Gleeson, Angus Walsh, Ping Koy Lam, and Syed M. Assad,

Quantum 8, 1382 (2024).

Discrete-variable (DV) quantum key distribution (QKD) based on single-photon detectors and sources have been successfully deployed for long-range secure key distribution. On the other hand,…

Steven T. Flammia and Ryan O’Donnell,

Quantum 8, 1381 (2024).

For quantum state tomography on rank-$r$ dimension-$d$ states, we show that $\widetilde{O}(r^{.5}d^{1.5}/\epsilon) \leq \widetilde{O}(d^2/\epsilon)$ copies suffice for accuracy $\epsilon$ with respe…

Hector Bombin, Daniel Litinski, Naomi Nickerson, Fernando Pastawski, and Sam Roberts,

Quantum 8, 1379 (2024).

There are several models of quantum computation which exhibit shared fundamental fault-tolerance properties. This article makes commonalities explicit by presenting these different models in…

Anand Natarajan and Chinmay Nirkhe,

Quantum 8, 1377 (2024).

It is a long-standing open question in quantum complexity theory whether the definition of $non-deterministic$ quantum computation requires quantum witnesses (QMA) or if classical witnesses su…

Alastair A. Abbott, Mehdi Mhalla, and Pierre Pocreau,

Quantum 8, 1376 (2024).

We investigate what quantum advantages can be obtained in multipartite non-cooperative games by studying how different types of quantum resources can lead to new Nash equilibria and improve…

Guang Hao Low, Vadym Kliuchnikov, and Luke Schaeffer,

Quantum 8, 1375 (2024).

Efficient synthesis of arbitrary quantum states and unitaries from a universal fault-tolerant gate-set e.g. Clifford+T is a key subroutine in quantum computation. As large quantum algorithms…

Dhrumil Patel, Patrick J. Coles, and Mark M. Wilde,

Quantum 8, 1374 (2024).

A semidefinite program (SDP) is a particular kind of convex optimization problem with applications in operations research, combinatorial optimization, quantum information science, and beyond…

Nikolas P. Breuckmann and Simon Burton,

Quantum 8, 1372 (2024).

We generalize the concept of folding from surface codes to CSS codes by considering certain dualities within them. In particular, this gives a general method to implement logical operations…

Oumarou Oumarou, Maximilian Scheurer, Robert M. Parrish, Edward G. Hohenstein, and Christian Gogolin,

Quantum 8, 1371 (2024).

We propose the regularized compressed double factorization (RC-DF) method to classically compute compressed representations of molecular Hamiltonians that enable efficient simulation with no…

Dominic W. Berry and Pedro C. S. Costa,

Quantum 8, 1369 (2024).

Time-dependent linear differential equations are a common type of problem that needs to be solved in classical physics. Here we provide a quantum algorithm for solving time-dependent linear…

Elia Zanoni, Thomas Theurer, and Gilad Gour,

Quantum 8, 1368 (2024).

Using local operations and classical communication (LOCC), entanglement can be manipulated but not created. However, entanglement can be $embezzled$. In this work, we completely characterize u…

Aby Philip, Soorya Rethinasamy, Vincent Russo, and Mark M. Wilde,

Quantum 8, 1366 (2024).

Quantifying entanglement is an important task by which the resourcefulness of a quantum state can be measured. Here, we develop a quantum algorithm that tests for and quantifies the separabi…

Á. Sáiz, J. Khalouf-Rivera, J. M. Arias, P. Pérez-Fernández, and J. Casado-Pascual,

Quantum 8, 1365 (2024).

Quantum phase transitions encompass a variety of phenomena that occur in quantum systems exhibiting several possible symmetries. Traditionally, these transitions are explored by continuously…

José Ramón Pareja Monturiol, David Pérez-García, and Alejandro Pozas-Kerstjens,

Quantum 8, 1364 (2024).

Tensor networks are factorizations of high-dimensional tensors into networks of smaller tensors. They have applications in physics and mathematics, and recently have been proposed as promisi…

Valérie Bettaque and Brian Swingle,

Quantum 8, 1362 (2024).

Motivated by the ground state structure of quantum models with all-to-all interactions such as mean-field quantum spin glass models and the Sachdev-Ye-Kitaev (SYK) model, we propose a tensor…

Federica Maria Surace, Pierre Fromholz, Francesco Scazza, and Marcello Dalmonte,

Quantum 8, 1359 (2024).

We propose a protocol for the scalable quantum simulation of SU($N$)$\times$U(1) lattice gauge theories with alkaline-earth like atoms in optical lattices in both one- and two-dimensional system…

Haimeng Zhao, Giuseppe Carleo, and Filippo Vicentini,

Quantum 8, 1358 (2024).

Quantum state reconstruction using Neural Quantum States has been proposed as a viable tool to reduce quantum shot complexity in practical applications, and its advantage over competing tech…

Charlie R. Hogg, Federico Cerisola, James D. Cresser, Simon A. R. Horsley, and Janet Anders,

Quantum 8, 1357 (2024).

The spin-boson model usually considers a spin coupled to a single bosonic bath. However, some physical situations require coupling of the spin to multiple environments. For example, spins in…

Roberto Ruiz, Alejandro Sopena, Max Hunter Gordon, Germán Sierra, and Esperanza López,

Quantum 8, 1356 (2024).

The Bethe ansatz represents an analytical method enabling the exact solution of numerous models in condensed matter physics and statistical mechanics. When a global symmetry is present, the…

Leonardo Assis Morais, Till Weinhold, Marcelo Pereira de Almeida, Joshua Combes, Markus Rambach, Adriana Lita, Thomas Gerrits, Sae Woo Nam, Andrew G. White, and Geoff Gillett,

Quantum 8, 1355 (2024).

Superconducting transition-edge sensors (TES) are extremely sensitive microcalorimeters used as photon detectors with unparalleled energy resolution. They have found application from measuri…

Adam Bene Watts, Anirban Chowdhury, Aidan Epperly, J. William Helton, and Igor Klep,

Quantum 8, 1352 (2024).

The Quantum Max Cut (QMC) problem has emerged as a test-problem for designing approximation algorithms for local Hamiltonian problems. In this paper we attack this problem using the algebrai…

Yiyun He, Fei Shi, and Xiande Zhang,

Quantum 8, 1349 (2024).

A set of orthogonal product states is strongly nonlocal if it is locally irreducible in every bipartition, which shows the phenomenon of strong quantum nonlocality without entanglement. Alth…

Benjamin F. Schiffer, Dyon van Vreumingen, Jordi Tura, and Stefano Polla,

Quantum 8, 1346 (2024).

Transitions out of the ground space limit the performance of quantum adiabatic algorithms, while hardware imperfections impose stringent limitations on the circuit depth. We propose an adiab…

Noah Berthusen and Daniel Gottesman,

Quantum 8, 1345 (2024).

Hypergraph product codes are a promising avenue to achieving fault-tolerant quantum computation with constant overhead. When embedding these and other constant-rate qLDPC codes into 2D, a si…

Alexander Cowtan and Simon Burton,

Quantum 8, 1344 (2024).

We define code maps between Calderbank-Shor-Steane (CSS) codes using maps between chain complexes, and describe code surgery between such codes using a specific colimit in the category of ch…

Francesco Preti, Michael Schilling, Sofiene Jerbi, Lea M. Trenkwalder, Hendrik Poulsen Nautrup, Felix Motzoi, and Hans J. Briegel,

Quantum 8, 1343 (2024).

Shortening quantum circuits is crucial to reducing the destructive effect of environmental decoherence and enabling useful algorithms. Here, we demonstrate an improvement in such compilation…

Fang-Fang Du, Gang Fan, and Xue-Mei Ren,

Quantum 8, 1342 (2024).

The decoherence effect caused by the coupling between the system and the environment undoubtedly leads to the errors in efficient implementations of two (or three) qubit logical gates in qua…

Jakub Czartowski, Karol Życzkowski, and Daniel Braun,

Quantum 8, 1341 (2024).

We propose an analogue of $\text{SU}(1,1)$ interferometry to measure rotation of a spin by using two-spin squeezed states. Attainability of the Heisenberg limit for the estimation of the rotat…

Antonio Anna Mele,

Quantum 8, 1340 (2024).

The Haar measure plays a vital role in quantum information, but its study often requires a deep understanding of representation theory, posing a challenge for beginners. This tutorial aims t…

Balázs Pozsgay and Ian M. Wanless,

Quantum 8, 1339 (2024).

Absolutely maximally entangled (AME) states of $k$ qudits (also known as perfect tensors) are quantum states that have maximal entanglement for all possible bipartitions of the sites/parties.…

Jerzy Paczos, Kacper Dębski, Piotr T. Grochowski, Alexander R. H. Smith, and Andrzej Dragan,

Quantum 8, 1338 (2024).

According to relativity, the reading of an ideal clock is interpreted as the elapsed proper time along its classical trajectory through spacetime. In contrast, quantum theory allows the asso…

Louis Paletta, Anthony Leverrier, Alain Sarlette, Mazyar Mirrahimi, and Christophe Vuillot,

Quantum 8, 1337 (2024).

Between NISQ (noisy intermediate scale quantum) approaches without any proof of robust quantum advantage and fully fault-tolerant quantum computation, we propose a scheme to achieve a provab…

Karen V. Hovhannisyan and Alberto Imparato,

Quantum 8, 1336 (2024).

Characterizing fluctuations of work in coherent quantum systems is notoriously problematic. Here we reveal the ultimate source of the problem by proving that ($\mathfrak{A}$) energy conservati…

Hui Wang, Flaminia Giacomini, Franco Nori, and Miles P. Blencowe,

Quantum 8, 1335 (2024).

In physics, it is crucial to identify operational measurement procedures to give physical meaning to abstract quantities. There has been significant effort to define time operationally using…

Julien du Crest, Francisco Garcia-Herrero, Mehdi Mhalla, Valentin Savin, and Javier Valls,

Quantum 8, 1334 (2024).

The inherent degeneracy of quantum low-density parity-check codes poses a challenge to their decoding, as it significantly degrades the error-correction performance of classical message-pass…

Victor Barizien, Pavel Sekatski, and Jean-Daniel Bancal,

Quantum 8, 1333 (2024).

Bell inequalities play a key role in certifying quantum properties for device-independent quantum information protocols. It is still a major challenge, however, to devise Bell inequalities t…

Edwin Peter Lobo, Jef Pauwels, and Stefano Pironio,

Quantum 8, 1332 (2024).

Losses in the transmission channel, which increase with distance, pose a major obstacle to photonics demonstrations of quantum nonlocality and its applications. Recently, Chaturvedi, Viola,…

Yifan Jia and Angela Capel,

Quantum 8, 1331 (2024).

Quantum Wielandt's inequality gives an optimal upper bound on the minimal length $k$ such that length-$k$ products of elements in a generating system span $M_n(\mathbb{C})$. It is conjectured that…

Andrea Coladangelo, Christian Majenz, and Alexander Poremba,

Quantum 8, 1330 (2024).

Copy-protection allows a software distributor to encode a program in such a way that it can be evaluated on any input, yet it cannot be "pirated" – a notion that is impossible to achieve in…

Priya J. Nadkarni, Praveen Jayakumar, Arpit Behera, and Shayan Srinivasa Garani,

Quantum 8, 1329 (2024).

We present the construction of standard entanglement-assisted (EA) qubit Reed-Muller (RM) codes and their tensor product variants from classical RM codes. We show that the EA RM codes obtain…

Philip Taranto, Marco Túlio Quintino, Mio Murao, and Simon Milz,

Quantum 8, 1328 (2024).

Memory is the fundamental form of temporal complexity: when present but uncontrollable, it manifests as non-Markovian noise; conversely, if controllable, memory can be a powerful resource fo…

Manuel G. Algaba, P. V. Sriluckshmy, Martin Leib, and Fedor Šimkovic IV,

Quantum 8, 1327 (2024).

We present a general strategy for mapping fermionic systems to quantum hardware with square qubit connectivity which yields low-depth quantum circuits, counted in the number of native two-qu…

Giovanni Di Fresco, Bernardo Spagnolo, Davide Valenti, and Angelo Carollo,

Quantum 8, 1326 (2024).

Measurement-induced phase transition arises from the competition between a deterministic quantum evolution and a repeated measurement process. We explore the measurement-induced phase transi…

Chris Cade and P. Marcos Crichigno,

Quantum 8, 1325 (2024).

We consider the complexity of the local Hamiltonian problem in the context of fermionic Hamiltonians with $\mathcal N=2 $ supersymmetry and show that the problem remains $\mathsf{QMA}$-complete.…

Zoltán Guba, István Finta, Ákos Budai, Lóránt Farkas, Zoltán Zimborás, and András Pályi,

Quantum 8, 1324 (2024).

In distributed computing, a Byzantine fault is a condition where a component behaves inconsistently, showing different symptoms to different components of the system. Consensus among the cor…

Michael Zurel, Cihan Okay, Robert Raussendorf, and Arne Heimendahl,

Quantum 8, 1323 (2024).

It was recently shown that a hidden variable model can be constructed for universal quantum computation with magic states on qubits. Here we show that this result can be extended, and a hidd…

Nikitas Stamatopoulos and William J. Zeng,

Quantum 8, 1322 (2024).

Pricing financial derivatives on quantum computers typically includes quantum arithmetic components which contribute heavily to the quantum resources required by the corresponding circuits.…

R. C. Souza Pimenta, G. H. dos Santos, A. B. Barreto, L. C. Celeri, and P. H. Souto Ribeiro,

Quantum 8, 1317 (2024).

Accelerated light has been demonstrated with laser light and diffraction. Within the diffracting field it is possible to identify a portion that carries most of the beam energy, which propag…

Marek Gluza,

Quantum 8, 1316 (2024).

This work proposes double-bracket iterations as a framework for obtaining diagonalizing quantum circuits. Their implementation on a quantum computer consists of interlacing evolutions genera…

Ram Krishna Patra, Sahil Gopalkrishna Naik, Edwin Peter Lobo, Samrat Sen, Tamal Guha, Some Sankar Bhattacharya, Mir Alimuddin, and Manik Banik,

Quantum 8, 1315 (2024).

We analyze utility of communication channels in absence of any short of quantum or classical correlation shared between the sender and the receiver. To this aim, we propose a class of two-pa…

David Fitzek, Robert S. Jonsson, Werner Dobrautz, and Christian Schäfer,

Quantum 8, 1313 (2024).

Variational quantum algorithms (VQAs) represent a promising approach to utilizing current quantum computing infrastructures. VQAs are based on a parameterized quantum circuit optimized in a…

Michael de Oliveira, Luís S. Barbosa, and Ernesto F. Galvão,

Quantum 8, 1312 (2024).

Several classes of quantum circuits have been shown to provide a quantum computational advantage under certain assumptions. The study of ever more restricted classes of quantum circuits capa…

Mariane Mangin-Brinet, Jing Zhang, Denis Lacroix, and Edgar Andres Ruiz Guzman,

Quantum 8, 1311 (2024).

We explore the possibility of adding complex absorbing potential at the boundaries when solving the one-dimensional real-time Schrödinger evolution on a grid using a quantum computer with a…

Craig Gidney,

Quantum 8, 1310 (2024).

In this paper, I cut the cost of Y basis measurement and initialization in the surface code by nearly an order of magnitude. Fusing twist defects diagonally across the surface code patch rea…

Noel T. Anderson, Jay-U Chung, Shelby Kimmel, Da-Yeon Koh, and Xiaohan Ye,

Quantum 8, 1309 (2024).

Quantum span program algorithms for function evaluation sometimes have reduced query complexity when promised that the input has a certain structure. We design a modified span program algori…

Titos Matsakos and Stuart Nield,

Quantum 8, 1306 (2024).

Monte Carlo (MC) simulations are widely used in financial risk management, from estimating value-at-risk (VaR) to pricing over-the-counter derivatives. However, they come at a significant co…

Thibaut Lacroix, Brendon W. Lovett, and Alex W. Chin,

Quantum 8, 1305 (2024).

Nanodevices exploiting quantum effects are critically important elements of future quantum technologies (QT), but their real-world performance is strongly limited by decoherence arising from…

Chao Yin and Andrew Lucas,

Quantum 8, 1303 (2024).

We show that it is possible to perform Heisenberg-limited metrology on GHZ-like states, in the presence of generic spatially local, possibly strong interactions during the measurement proces…

Matthias C. Löbl, Stefano Paesani, and Anders S. Sørensen,

Quantum 8, 1302 (2024).

We develop an architecture for measurement-based quantum computing using photonic quantum emitters. The architecture exploits spin-photon entanglement as resource states and standard Bell me…

David Green, Peter Huston, Kyle Kawagoe, David Penneys, Anup Poudel, and Sean Sanford,

Quantum 8, 1301 (2024).

Boundaries of Walker-Wang models have been used to construct commuting projector models which realize chiral unitary modular tensor categories (UMTCs) as boundary excitations. Given a UMTC…

Jacob Bringewatt, Jonathan Kunjummen, and Niklas Mueller,

Quantum 8, 1300 (2024).

Randomized measurement protocols, including classical shadows, entanglement tomography, and randomized benchmarking are powerful techniques to estimate observables, perform state tomography,…

Ignacio García-Mata, Rodrigo G. Cortiñas, Xu Xiao, Jorge Chávez-Carlos, Victor S. Batista, Lea F. Santos, and Diego A. Wisniacki,

Quantum 8, 1298 (2024).

Parametric gates and processes engineered from the perspective of the static effective Hamiltonian of a driven system are central to quantum technology. However, the perturbative expansions…

Javier Gonzalez-Conde, Thomas W. Watts, Pablo Rodriguez-Grasa, and Mikel Sanz,

Quantum 8, 1297 (2024).

Loading functions into quantum computers represents an essential step in several quantum algorithms, such as quantum partial differential equation solvers. Therefore, the inefficiency of thi…

Gian Gentinetta, Friederike Metz, and Giuseppe Carleo,

Quantum 8, 1296 (2024).

Simulating the dynamics of large quantum systems is a formidable yet vital pursuit for obtaining a deeper understanding of quantum mechanical phenomena. While quantum computers hold great pr…

Kevin Slagle,

Quantum 8, 1295 (2024).

Although local Hamiltonians exhibit local time dynamics, this locality is not explicit in the Schrödinger picture in the sense that the wavefunction amplitudes do not obey a local equation o…

L. Peri, G. A. Oakes, L. Cochrane, C. J. B. Ford, and M. F. Gonzalez-Zalba,

Quantum 8, 1294 (2024).

Semiconductor quantum dots operated dynamically are the basis of many quantum technologies such as quantum sensors and computers. Hence, modelling their electrical properties at microwave fr…

Matteo Ippoliti,

Quantum 8, 1293 (2024).

We study classical shadows protocols based on randomized measurements in $n$-qubit entangled bases, generalizing the random Pauli measurement protocol ($n = 1$). We show that entangled measureme…

Antonio Sannia, Rodrigo Martínez-Peña, Miguel C. Soriano, Gian Luca Giorgi, and Roberta Zambrini,

Quantum 8, 1291 (2024).

Dissipation induced by interactions with an external environment typically hinders the performance of quantum computation, but in some cases can be turned out as a useful resource. We show t…

Andreas Bauer,

Quantum 8, 1288 (2024).

We propose a unifying paradigm for analyzing and constructing topological quantum error correcting codes as dynamical circuits of geometrically local channels and measurements. To this end,…

Samson Wang, Piotr Czarnik, Andrew Arrasmith, M. Cerezo, Lukasz Cincio, and Patrick J. Coles,

Quantum 8, 1287 (2024).

Variational Quantum Algorithms (VQAs) are often viewed as the best hope for near-term quantum advantage. However, recent studies have shown that noise can severely limit the trainability of…

Cornelia Spee and Tristan Kraft,

Quantum 8, 1286 (2024).

Recent advances have led towards first prototypes of quantum networks in which entanglement is distributed by sources producing bipartite entangled states. This raises the question of which…

Javier Argüello-Luengo, Manfred J. Mark, Francesca Ferlaino, Maciej Lewenstein, Luca Barbiero, and Sergi Julià-Farré,

Quantum 8, 1285 (2024).

Thouless pumping represents a powerful concept to probe quantized topological invariants in quantum systems. We explore this mechanism in a generalized Rice-Mele Fermi-Hubbard model characte…

David Schmid, John H. Selby, Matthew F. Pusey, and Robert W. Spekkens,

Quantum 8, 1283 (2024).

It is useful to have a criterion for when the predictions of an operational theory should be considered classically explainable. Here we take the criterion to be that the theory admits of a…

Daniel Bochen Tan, Dolev Bluvstein, Mikhail D. Lukin, and Jason Cong,

Quantum 8, 1281 (2024).

Dynamically field-programmable qubit arrays (DPQA) have recently emerged as a promising platform for quantum information processing. In DPQA, atomic qubits are selectively loaded into arrays…

Daniel Collins,

Quantum 8, 1280 (2024).

Teleportation allows Alice to send a pre-prepared quantum state to Bob using only pre-shared entanglement and classical communication. Here we show that it is possible to teleport a state wh…

Maria-Andreea Filip, David Muñoz Ramo, and Nathan Fitzpatrick,

Quantum 8, 1278 (2024).

Subspace diagonalisation methods have appeared recently as promising means to access the ground state and some excited states of molecular Hamiltonians by classically diagonalising small mat…

Chia-Yi Ju, Adam Miranowicz, Yueh-Nan Chen, Guang-Yin Chen, and Franco Nori,

Quantum 8, 1277 (2024).

Studies have shown that the Hilbert spaces of non-Hermitian systems require nontrivial metrics. Here, we demonstrate how evolution dimensions, in addition to time, can emerge naturally from…

Penghua Chen, Bowen Yan, and Shawn X. Cui,

Quantum 8, 1276 (2024).

We propose a systematic and efficient quantum circuit composed solely of Clifford gates for simulating the ground state of the surface code model. This approach yields the ground state of th…

Roeland Wiersema, Dylan Lewis, David Wierichs, Juan Carrasquilla, and Nathan Killoran,

Quantum 8, 1275 (2024).

Variational quantum algorithms use non-convex optimization methods to find the optimal parameters for a parametrized quantum circuit in order to solve a computational problem. The choice of…

Jean-Yves Desaules, Guo-Xian Su, Ian P. McCulloch, Bing Yang, Zlatko Papić, and Jad C. Halimeh,

Quantum 8, 1274 (2024).

The quantum simulation of gauge theories on synthetic quantum matter devices has gained a lot of traction in the last decade, making possible the observation of a range of exotic quantum man…

Roy Barzel, Mustafa Gündoğan, Markus Krutzik, Dennis Rätzel, and Claus Lämmerzahl,

Quantum 8, 1273 (2024).

We investigate the effect of entanglement dynamics due to gravity – the basis of a mechanism of universal decoherence – for photonic states and quantum memories in Mach-Zehnder and Hong-Ou-M…

David Pérez-García, Leonardo Santilli, and Miguel Tierz,

Quantum 8, 1271 (2024).

We uncover a novel dynamical quantum phase transition, using random matrix theory and its associated notion of planar limit. We study it for the isotropic XY Heisenberg spin chain. For this,…

Nicky Kai Hong Li, Cornelia Spee, Martin Hebenstreit, Julio I. de Vicente, and Barbara Kraus,

Quantum 8, 1270 (2024).

The study of state transformations by spatially separated parties with local operations assisted by classical communication (LOCC) plays a crucial role in entanglement theory and its applica…

Aleksandra Krawiec, Łukasz Pawela, and Zbigniew Puchała,

Quantum 8, 1269 (2024).

We study the discrimination of von Neumann measurements in the scenario when we are given a reference measurement and some other measurement. The aim of the discrimination is to determine wh…

Zhao Zhang,

Quantum 8, 1268 (2024).

Quantum loop models are well studied objects in the context of lattice gauge theories and topological quantum computing. They usually carry long range entanglement that is captured by the to…

Nicolas Gisin and Flavio Del Santo,

Quantum 8, 1267 (2024).

Naive attempts to put together relativity and quantum measurements lead to signaling between space-like separated regions. In QFT, these are known as $\textit{impossible measurements}$. We sho…

Gumaro Rendon, Jacob Watkins, and Nathan Wiebe,

Quantum 8, 1266 (2024).

Quantum metrology allows for measuring properties of a quantum system at the optimal Heisenberg limit. However, when the relevant quantum states are prepared using digital Hamiltonian simula…

El Amine Cherrat, Iordanis Kerenidis, Natansh Mathur, Jonas Landman, Martin Strahm, and Yun Yvonna Li,

Quantum 8, 1265 (2024).

In this work, quantum transformers are designed and analysed in detail by extending the state-of-the-art classical transformer neural network architectures known to be very performant in nat…

Sean Greenaway, Adam Smith, Florian Mintert, and Daniel Malz,

Quantum 8, 1263 (2024).

We experimentally assess the suitability of transmon qubits with fixed frequencies and fixed interactions for the realization of analogue quantum simulations of spin systems. We test a set o…

Daniel Burgarth, Paolo Facchi, Robin Hillier, and Marilena Ligabò,

Quantum 8, 1262 (2024).

The interaction between light and matter is one of the oldest research areas of quantum mechanics, and a field that just keeps on delivering new insights and applications. With the arrival o…

Xie-Hang Yu, Zhiyuan Wang, and Pavel Kos,

Quantum 8, 1260 (2024).

Quantum dynamics with local interactions in lattice models display rich physics, but is notoriously hard to study. Dual-unitary circuits allow for exact answers to interesting physical quest…

Emiel Koridon, Joana Fraxanet, Alexandre Dauphin, Lucas Visscher, Thomas E. O’Brien, and Stefano Polla,

Quantum 8, 1259 (2024).

Conical intersections are topologically protected crossings between the potential energy surfaces of a molecular Hamiltonian, known to play an important role in chemical processes such as ph…

Kaiwen Gui, Alexander M. Dalzell, Alessandro Achille, Martin Suchara, and Frederic T. Chong,

Quantum 8, 1257 (2024).

We propose a novel deterministic method for preparing arbitrary quantum states. When our protocol is compiled into CNOT and arbitrary single-qubit gates, it prepares an $N$-dimensional state i…

Julius Arthur Bittermann, Lukas Bulla, Sebastian Ecker, Sebastian Philipp Neumann, Matthias Fink, Martin Bohmann, Nicolai Friis, Marcus Huber, and Rupert Ursin,

Quantum 8, 1256 (2024).

Quantum technologies have matured to the point that we can test fundamental quantum phenomena under extreme conditions. Specifically, entanglement, a cornerstone of modern quantum informatio…

Ming Ji and Holger F. Hofmann,

Quantum 8, 1255 (2024).

In quantum theory, a measurement context is defined by an orthogonal basis in a Hilbert space, where each basis vector represents a specific measurement outcome. The precise quantitative rel…

Robert J. Banks, Ehsan Haque, Farah Nazef, Fatima Fethallah, Fatima Ruqaya, Hamza Ahsan, Het Vora, Hibah Tahir, Ibrahim Ahmad, Isaac Hewins, Ishaq Shah, Krish Baranwal, Mannan Arora, Mateen Asad, Mubasshirah Khan, Nabian Hasan, Nuh Azad, Salgai Fedaiee, Shakeel Majeed, Shayam Bhuyan, Tasfia Tarannum, Yahya Ali, Dan E. Browne, and P. A. Warburton,

Quantum 8, 1254 (2024).

By exploiting the link between time-independent Hamiltonians and thermalisation, heuristic predictions on the performance of continuous-time quantum walks for MAX-CUT are made. The resulting…

Robert J. Banks, Dan E. Browne, and P.A. Warburton,

Quantum 8, 1253 (2024).

We propose a new design heuristic to tackle combinatorial optimisation problems, inspired by Hamiltonians for optimal state-transfer. The result is a rapid approximate optimisation algorithm…

Huo Chen, Niladri Gomes, Siyuan Niu, and Wibe Albert de Jong,

Quantum 8, 1252 (2024).

Emerging quantum hardware provides new possibilities for quantum simulation. While much of the research has focused on simulating closed quantum systems, the real-world quantum systems are m…

David Gosset, Daniel Grier, Alex Kerzner, and Luke Schaeffer,

Quantum 8, 1251 (2024).

A general quantum circuit can be simulated classically in exponential time. If it has a planar layout, then a tensor-network contraction algorithm due to Markov and Shi has a runtime exponen…

Natália S. Móller, Bruna Sahdo, and Nelson Yokomizo,

Quantum 8, 1248 (2024).

In the absence of a complete theory of quantum gravity, phenomenological models built upon minimal assumptions have been explored for the analysis of possible quantum effects in gravitationa…

Stavros Efthymiou, Alvaro Orgaz-Fuertes, Rodolfo Carobene, Juan Cereijo, Andrea Pasquale, Sergi Ramos-Calderer, Simone Bordoni, David Fuentes-Ruiz, Alessandro Candido, Edoardo Pedicillo, Matteo Robbiati, Yuanzheng Paul Tan, Jadwiga Wilkens, Ingo Roth, José Ignacio Latorre, and Stefano Carrazza,

Quantum 8, 1247 (2024).

We present $\texttt{Qibolab}$, an open-source software library for quantum hardware control integrated with the $\texttt{Qibo}$ quantum computing middleware framework. $\texttt{Qibolab}$ provides…

Leevi Leppäjärvi and Michal Sedlák,

Quantum 8, 1246 (2024).

Quantum instruments describe outcome probability as well as state change induced by measurement of a quantum system. Incompatibility of two instruments, i. e. the impossibility to realize th…

Massimo Bortone, Yannic Rath, and George H. Booth,

Quantum 8, 1245 (2024).

We present a generalized framework to adapt universal quantum state approximators, enabling them to satisfy rigorous normalization and autoregressive properties. We also introduce filters as…

Sahar Atallah, Michael Garn, Sania Jevtic, Yukuan Tao, and Shashank Virmani,

Quantum 8, 1243 (2024).

We provide new examples of pure entangled systems related to cluster state quantum computation that can be efficiently simulated classically. In cluster state quantum computation input qubit…

José D. Guimarães, Mikhail I. Vasilevskiy, and Luís S. Barbosa,

Quantum 8, 1242 (2024).

Classical non-perturbative simulations of open quantum systems' dynamics face several scalability problems, namely, exponential scaling of the computational effort as a function of either th…

Luca Apadula, Alessandro Bisio, and Paolo Perinotti,

Quantum 8, 1241 (2024).

Quantum processes with indefinite causal structure emerge when we wonder which are the most general evolutions, allowed by quantum theory, of a set of local systems which are not assumed to…

Rafael Wagner, Anita Camillini, and Ernesto F. Galvão,

Quantum 8, 1240 (2024).

We analyse nonclassical resources in interference phenomena using generalized noncontextuality inequalities and basis-independent coherence witnesses. We use recently proposed inequalities t…

Chae-Yeun Park and Nathan Killoran,

Quantum 8, 1239 (2024).

Variational quantum algorithms, which combine highly expressive parameterized quantum circuits (PQCs) and optimization techniques in machine learning, are one of the most promising applicati…

Robert H. Jonsson and Johannes Knörzer,

Quantum 8, 1237 (2024).

The interaction between localized emitters and quantum fields, both in relativistic settings and in the case of ultra-strong couplings, requires non-perturbative methods beyond the rotating-…

Shuheng Liu, Matteo Fadel, Qiongyi He, Marcus Huber, and Giuseppe Vitagliano,

Quantum 8, 1236 (2024).

High-dimensional entanglement has been identified as an important resource in quantum information processing, and also as a main obstacle for simulating quantum systems. Its certification is…

Marcin Rudziński, Adam Burchardt, and Karol Życzkowski,

Quantum 8, 1234 (2024).

Spin anticoherent states acquired recently a lot of attention as the most "quantum" states. Some coherent and anticoherent spin states are known as optimal quantum rotosensors. In this work,…

Narayanan Rengaswamy, Nithin Raveendran, Ankur Raina, and Bane Vasić,

Quantum 8, 1233 (2024).

Recent constructions of quantum low-density parity-check (QLDPC) codes provide optimal scaling of the number of logical qubits and the minimum distance in terms of the code length, thereby o…

Xiao-Yu Li, Qin-Sheng Zhu, Yong Hu, Hao Wu, Guo-Wu Yang, Lian-Hui Yu, and Geng Chen,

Quantum 8, 1232 (2024).

The Hidden Quantum Markov Model (HQMM) has significant potential for analyzing time-series data and studying stochastic processes in the quantum domain as an upgrading option with potential…

Shree Hari Sureshbabu, Dylan Herman, Ruslan Shaydulin, Joao Basso, Shouvanik Chakrabarti, Yue Sun, and Marco Pistoia,

Quantum 8, 1231 (2024).

Quantum Approximate Optimization Algorithm (QAOA) is a leading candidate algorithm for solving combinatorial optimization problems on quantum computers. However, in many cases QAOA requires…

Pablo M. Poggi and Manuel H. Muñoz-Arias,

Quantum 8, 1229 (2024).

We study the competing effects of collective generalized measurements and interaction-induced scrambling in the dynamics of an ensemble of spin-1/2 particles at the level of quantum trajecto…

Silvia Pappalardi, Laura Foini, and Jorge Kurchan,

Quantum 8, 1227 (2024).

We discuss the construction of a microcanonical projection WOW of a quantum operator O induced by an energy window filter W, its spectrum, and the retrieval of canonical many-time correlatio…

Christoph Sünderhauf, Earl Campbell, and Joan Camps,

Quantum 8, 1226 (2024).

The cost of data input can dominate the run-time of quantum algorithms. Here, we consider data input of arithmetically structured matrices via $\textit{block encoding}$ circuits, the input mod…

Gian Gentinetta, Arne Thomsen, David Sutter, and Stefan Woerner,

Quantum 8, 1225 (2024).

Quantum support vector machines employ quantum circuits to define the kernel function. It has been shown that this approach offers a provable exponential speedup compared to any known classi…

Lucas B. Vieira, Simon Milz, Giuseppe Vitagliano, and Costantino Budroni,

Quantum 8, 1224 (2024).

We introduce a framework to compute upper bounds for temporal correlations achievable in open quantum system dynamics, obtained by repeated measurements on the system. As these correlations…

V. Stepanyan and A.E. Allahverdyan,

Quantum 8, 1223 (2024).

Quantum mechanics does not provide any ready recipe for defining energy density in space, since the energy and coordinate do not commute. To find a well-motivated energy density, we start fr…

Huangjun Zhu, Yunting Li, and Tianyi Chen,

Quantum 8, 1221 (2024).

Ground states of local Hamiltonians are of key interest in many-body physics and also in quantum information processing. Efficient verification of these states are crucial to many applicatio…

Jingwei Wen, Zhengan Wang, Chitong Chen, Junxiang Xiao, Hang Li, Ling Qian, Zhiguo Huang, Heng Fan, Shijie Wei, and Guilu Long,

Quantum 8, 1219 (2024).

Utilizing quantum computer to investigate quantum chemistry is an important research field nowadays. In addition to the ground-state problems that have been widely studied, the determination…

David Schmid,

Quantum 8, 1217 (2024).

The notion of macrorealism was introduced by Leggett and Garg in an attempt to capture our intuitive conception of the macroscopic world, which seems difficult to reconcile with our knowledg…