Quantum Simulation of Coupled Harmonic Oscillators: From Theory to Implementation

This paper bridges the gap between theory and implementation for the quantum simulation of coupled harmonic oscillators by developing and benchmarking three distinct algorithmic realizations on the Classiq platform, demonstrating that complex initial state preparation can be circumvented while providing concrete resource estimates and physical applications for achieving practical quantum advantage.

Viraj Dsouza, Weronika Golletz, Dimitrios Kranas, Bakhao Dioum, Vardaan Sahgal, Eden Schirman2026-03-06⚛️ quant-ph

Improved Decoding of Quantum Tanner Codes Using Generalized Check Nodes

This paper proposes an enhanced iterative belief propagation decoder for quantum Tanner codes that groups check nodes into generalized checks decoded via maximum a posteriori methods, demonstrating significant performance gains over existing decoders in finite-length settings while identifying limited benefits for other qLDPC code families through both empirical results and theoretical cycle analysis.

Olai \AA. Mostad, Eirik Rosnes, Hsuan-Yin Lin2026-03-06⚛️ quant-ph

Ansatz-Free Learning of Lindbladian Dynamics In Situ

This paper introduces the first sample-efficient, ancilla-free protocol for learning sparse Lindbladian generators of open quantum systems without requiring prior assumptions about interaction structure or locality, utilizing only product-state preparations and Pauli measurements to enable scalable characterization of unknown error mechanisms.

Petr Ivashkov, Nikita Romanov, Weiyuan Gong, Andi Gu, Hong-Ye Hu, Susanne F. Yelin2026-03-06⚛️ quant-ph

Gravitational back-reaction is magical

This paper investigates the relationship between non-local magic and entanglement in quantum many-body systems, establishing bounds on classical simulation hardness and conjecturing a linear scaling in conformal field theories, while proving that in holographic duals, non-local magic vanishes precisely when gravitational back-reaction is absent and is approximately equal to the rate of change of minimal surface area with respect to cosmic brane tension.

ChunJun Cao, Gong Cheng, Alioscia Hamma + 3 more2026-03-05⚛️ quant-ph

Barycentric bounds on the error exponents of quantum hypothesis exclusion

This paper establishes new, improved, single-letter upper bounds on the error exponents for quantum state and channel exclusion tasks by introducing a multivariate barycentric Chernoff divergence, which also yields the first efficiently computable bound for symmetric binary channel discrimination and solves the exact error exponent for classical channel exclusion.

Kaiyuan Ji, Hemant K. Mishra, Milán Mosonyi + 1 more2026-03-05⚛️ quant-ph

Near-optimal coherent state discrimination via continuously labelled non-Gaussian measurements

This paper demonstrates that near-optimal discrimination of coherent states, surpassing the traditional Gaussian limit and approaching the Helstrom bound, can be achieved using continuously labelled non-Gaussian measurements via non-Gaussian unitary operations with homodyne detection or orthogonal polynomials, thereby eliminating the necessity for discrete photon detection.

James Moran, Spiros Kechrimparis, Hyukjoon Kwon2026-03-05⚛️ quant-ph

Pure state entanglement and von Neumann algebras

This paper extends Nielsen's Theorem on LOCC ordering to bipartite quantum systems described by commuting von Neumann algebras, establishing a one-to-one correspondence between the classification of factors (types I, II, and III) and their operational entanglement properties, such as infinite single-shot entanglement and the ability to transition between arbitrary pure states with arbitrary precision.

Lauritz van Luijk, Alexander Stottmeister, Reinhard F. Werner + 1 more2026-03-05⚛️ quant-ph