Quantum

Paper

Quantized Markov Chain Couplings that Prepare Qsamples

Kristan Temme and Pawel Wocjan,

Quantum 9, 1951 (2025).

We present a novel approach to quantizing Markov chains. The approach is based on the Markov chain coupling method, which is frequently used to prove fast mixing. Given a particular coupling…

Paper

Performance Analysis of Quantum CSS Error-Correcting Codes via MacWilliams Identities

Diego Forlivesi, Lorenzo Valentini, and Marco Chiani,

Quantum 9, 1950 (2025).

We analyze the performance of quantum stabilizer codes, one of the most important classes for practical implementations, on both symmetric and asymmetric quantum channels. To this aim, we fi…

Paper

Probes of Full Eigenstate Thermalization in Ergodicity-Breaking Quantum Circuits

Gabriel O. Alves, Felix Fritzsch, and Pieter W. Claeys,

Quantum 9, 1949 (2025).

The eigenstate thermalization hypothesis (ETH) is the leading interpretation in our current understanding of quantum thermalization. Recent results uncovered strong connections between quant…

Paper

Quantum Communication Networks Enhanced by Distributed Quantum Memories

Xiangyi Meng, Nicolò Lo Piparo, Kae Nemoto, and István A. Kovács,

Quantum 9, 1948 (2025).

Building large-scale quantum communication networks has its unique challenges. Here, we demonstrate that a network-wide synergistic usage of quantum memories distributed in a quantum communi…

Paper

Entangled Subspaces through Algebraic Geometry

Masoud Gharahi and Stefano Mancini,

Quantum 9, 1947 (2025).

We propose an algebraic geometry-inspired approach for constructing entangled subspaces within the Hilbert space of a multipartite quantum system. Specifically, our method employs a modified…

Paper

GPU-accelerated Effective Hamiltonian Calculator

Abhishek Chakraborty, Taylor L. Patti, Brucek Khailany, Andrew N. Jordan, and Anima Anandkumar,

Quantum 9, 1946 (2025).

Effective Hamiltonian calculations for large quantum systems can be both analytically intractable and numerically expensive using standard techniques. In this manuscript, we present numerica…

Paper

A Novel Stabilizer-based Entanglement Distillation Protocol for Qudits

Christopher Popp, Tobias C. Sutter, and Beatrix C. Hiesmayr,

Quantum 9, 1945 (2025).

Entanglement distillation, the process of converting weakly entangled states into maximally entangled ones using Local Operations and Classical Communication (LOCC), is pivotal for robust en…

Paper

Emergent Liouvillian exceptional points from exact principles

Shishir Khandelwal and Gianmichele Blasi,

Quantum 9, 1944 (2025).

Recent years have seen a surge of interest in exceptional points in open quantum systems. The natural approach in this area has been the use of Markovian master equations. While the resultin…

Paper

Towards practical secure delegated quantum computing with semi-classical light

Boris Bourdoncle, Pierre-Emmanuel Emeriau, Paul Hilaire, Shane Mansfield, Luka Music, and Stephen Wein,

Quantum 9, 1943 (2025).

Secure Delegated Quantum Computation (SDQC) protocols are a vital piece of the future quantum information processing global architecture since they allow end-users to perform their valuable…

Paper

Exploiting many-body localization for scalable variational quantum simulation

Chenfeng Cao, Yeqing Zhou, Swamit Tannu, Nic Shannon, and Robert Joynt,

Quantum 9, 1942 (2025).

Variational quantum algorithms (VQAs) represent a promising pathway toward achieving practical quantum advantage on near-term hardware. Despite this promise, for generic, expressive ansätze,…

Paper

Finite-Key Analysis of Quantum Key Distribution with Characterized Devices Using Entropy Accumulation

Ian George, Jie Lin, Thomas van Himbeeck, Kun Fang, and Norbert Lütkenhaus,

Quantum 9, 1941 (2025).

The Entropy Accumulation Theorem (EAT) was introduced to significantly improve the finite-size rates for device-independent quantum information processing tasks such as device-independent qu…

Paper

Short remarks on shallow unitary circuits

Jeongwan Haah,

Quantum 9, 1940 (2025).

(i) We point out that every local unitary circuit of depth smaller than the linear system size is easily distinguished from a global Haar random unitary if there is a conserved quantity that…

Paper

Proposal for a Bell Test with Entangled Atoms of Different Mass

X. T. Yan, S. Kannan, Y. S. Athreya, A. G. Truscott, and S. S. Hodgman,

Quantum 9, 1939 (2025).

We propose a Bell test experiment using momentum-entangled atom pairs of different masses, specifically metastable helium isotopes ${}^{3}He^{*}$ and ${}^{4}He^{*}$, though the method extends to…

Paper

Purely quantum memory in closed systems observed via imperfect measurements

Jorge Tabanera-Bravo and Aljaz Godec,

Quantum 9, 1938 (2025).

The detection and quantification of non-Markovianity, a.k.a. memory, in quantum systems is a central problem in the theory of open quantum systems. There memory is as a result of the interac…

Paper

Phase error rate estimation in QKD with imperfect detectors

Devashish Tupkary, Shlok Nahar, Pulkit Sinha, and Norbert Lütkenhaus,

Quantum 9, 1937 (2025).

We present a finite-size security proof of the decoy-state BB84 QKD protocol against coherent attacks, using entropic uncertainty relations, for imperfect detectors. We apply this result to…

Paper

LUCI in the Surface Code with Dropouts

Dripto M. Debroy, Matt McEwen, Craig Gidney, Noah Shutty, and Adam Zalcman,

Quantum 9, 1936 (2025).

Recently, usage of detecting regions facilitated the discovery of new circuits for fault-tolerantly implementing the surface code. Building on these ideas, we present LUCI, a framework for c…

Category: Paper