Quantum

Quantum has published 2260 Papers in 10 Volumes, as well as 87 Views in Quantum Views.

Efficient Classical Simulation of the DQC1 Circuit with Zero Discord

Shalin Jose, Akshay Kannan Sairam, and Anil Shaji,

Quantum 9, 1895 (2025).

A path for efficient classical simulation of the DQC1 circuit that estimates the trace of an implementable unitary under the zero discord condition [17] is presented. This result reinforces…

Paper

Quantum bounds for compiled XOR games and $d$-outcome CHSH games

Matilde Baroni, Quoc-Huy Vu, Boris Bourdoncle, Eleni Diamanti, Damian Markham, and Ivan Šupić,

Quantum 9, 1894 (2025).

Nonlocal games play a crucial role in quantum information theory and have numerous applications in certification and cryptographic protocols. Kalai et al. (STOC 2023) introduced a procedure…

Paper

Effectiveness of the syndrome extraction circuit with flag qubits on IBM quantum hardware

Younghun Kim, Hansol Kim, Jeongsoo Kang, Wonjae Choi, and Younghun Kwon,

Quantum 9, 1893 (2025).

Large-scale quantum circuits are required to exploit the advantages of quantum computers. Despite significant advancements in quantum hardware, scalability remains a challenge, with errors a…

Paper

Missing Puzzle Pieces in the Performance Landscape of the Quantum Approximate Optimization Algorithm

Elisabeth Wybo and Martin Leib,

Quantum 9, 1892 (2025).

We consider the maximum cut and maximum independent set problems on random regular graphs in the infinite-size limit, and calculate the energy densities achieved by QAOA for high degrees up…

Paper

Indefinite causal order strategy does not improve the estimation of group action

Masahito Hayashi,

Quantum 9, 1891 (2025).

We consider estimation of unknown unitary operation when the set of possible unitary operations is given by a projective unitary representation of a compact group. We show that neither indef…

Paper

A Mathematical Structure for Amplitude-Mixing Error-Transparent Gates for Binomial Codes

Owen C. Wetherbee, Saswata Roy, Baptiste Royer, and Valla Fatemi,

Quantum 9, 1890 (2025).

Bosonic encodings of quantum information offer hardware-efficient, noise-biased approaches to quantum error correction relative to qubit register encodings. Implementations have focused in p…

Paper

Quantum circuit synthesis with SQiSW

Jialiang Tang, Jialin Zhang, and Xiaoming Sun,

Quantum 9, 1889 (2025).

The primary objective of quantum circuit synthesis is to efficiently and accurately realize specific quantum algorithms or operations utilizing a predefined set of quantum gates, while also…

Paper

Observable-projected ensembles

Alexey Milekhin and Sara Murciano,

Quantum 9, 1888 (2025).

Measurements in many-body quantum systems can generate non-trivial phenomena, such as preparation of long-range entangled states, dynamical phase transitions, or measurement-altered critical…

Paper

The discrete adiabatic quantum linear system solver has lower constant factors than the randomized adiabatic solver

Pedro C.S. Costa, Dong An, Ryan Babbush, and Dominic Berry,

Quantum 9, 1887 (2025).

The solution of linear systems of equations is the basis of many other quantum algorithms, and recent results provided an algorithm with optimal scaling in both the condition number $\kappa$ a…

Paper

Error Correction in Dynamical Codes

Esther Xiaozhen Fu and Daniel Gottesman,

Quantum 9, 1886 (2025).

We ask what is the general framework for a quantum error correcting code that is defined by a sequence of measurements. Recently, there has been much interest in Floquet codes and space-time…

Paper

Conditional disclosure of secrets with quantum resources

Vahid R. Asadi, Kohdai Kuroiwa, Debbie Leung, Alex May, Sabrina Pasterski, and Chris Waddell,

Quantum 9, 1885 (2025).

The conditional disclosure of secrets (CDS) primitive is among the simplest cryptographic settings in which to study the relationship between communication, randomness, and security. CDS inv…

Paper

Quantum Error Correction resilient against Atom Loss

Hugo Perrin, Sven Jandura, and Guido Pupillo,

Quantum 9, 1884 (2025).

We investigate quantum error correction protocols for neutral atoms quantum processors in the presence of atom loss. We complement the surface code with loss detection units (LDU) and analyz…

Paper

On the average-case complexity of learning output distributions of quantum circuits

Alexander Nietner, Marios Ioannou, Ryan Sweke, Richard Kueng, Jens Eisert, Marcel Hinsche, and Jonas Haferkamp,

Quantum 9, 1883 (2025).

In this work, we show that learning the output distributions of brickwork random quantum circuits is average-case hard in the statistical query model. This learning model is widely used as a…

Paper

Deep-Circuit QAOA

Gereon Koßmann, Lennart Binkowski, Lauritz van Luijk, Timo Ziegler, and René Schwonnek,

Quantum 9, 1882 (2025).

Paper

Classical simulation and quantum resource theory of non-Gaussian optics

Oliver Hahn, Ryuji Takagi, Giulia Ferrini, and Hayata Yamasaki,

Quantum 9, 1881 (2025).

We propose efficient algorithms for classically simulating Gaussian unitaries and measurements applied to non-Gaussian initial states. The constructions are based on decomposing the non-Gaus…

Paper

Shadows and subsystems of generalized probabilistic theories: when tomographic incompleteness is not a loophole for contextuality proofs

David Schmid, John H. Selby, Vinicius P. Rossi, Roberto D. Baldijão, and Ana Belén Sainz,

Quantum 9, 1880 (2025).

It is commonly believed that failures of tomographic completeness undermine assessments of nonclassicality in noncontextuality experiments. In this work, we study how such failures can indee…