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Papers

Live trends in quantum computing research, updated daily from arXiv.

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27,980

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13,202 papers in 12 months (+3% vs prior quarter)

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27,980 papers found

The fermion sign problem in Gauss law sectors of quantum link models with dynamical matter

Pallabi Dey, Debasish Banerjee, Emilie Huffman·Dec 16, 2025

The fermion sign problem poses a formidable challenge to the use of Monte Carlo methods for lattice gauge theories with dynamical fermionic matter fields. A meron cluster algorithm recently formulated for gauge fields represented as spin-$\frac{1}{2}...

hep-latcond-mat.str-elhep-thQuantum Physics

Extreme non-negative Wigner functions

Zacharie Van Herstraeten, Jack Davis, Nuno C. Dias +3 more·Dec 16, 2025

Providing an operational characterization of the Wigner-positive states (WPS), i.e., the set of quantum states with non-negative Wigner function, is a longstanding open problem. For pure states, the only WPS are Gaussian states, but the situation is ...

Quantum Physics

Strong-to-weak symmetry breaking in monitored dipole conserving quantum circuits

Caterina Zerba, Sarang Gopalakrishnan, Michael Knap·Dec 16, 2025

We explore the information-theoretic phases of monitored quantum circuits subject to dynamics that conserves both charge and dipole moment, as well as measurements of the local charge density. Explicitly, both charge and dipole-moment conservation ar...

Quantum Physicscond-mat.stat-mech

Growth and spreading of quantum resources under random circuit dynamics

Sreemayee Aditya, Xhek Turkeshi, Piotr Sierant·Dec 16, 2025

Quantum many-body dynamics generate nonclassical correlations naturally described by quantum resource theories. Quantum magic resources (or nonstabilizerness) capture deviation from classically simulable stabilizer states, while coherence and fermion...

Quantum Physicscond-mat.stat-mech

Symmetric Dicke States as Optimal Probes for Wave-Like Dark Matter

Ping He, Jing Shu, Bin Xu +1 more·Dec 16, 2025

We identify symmetric Dicke states as the optimal quantum probes for distributed sensing of wave-like dark-matter fields. Within an ensemble-averaged quantum-metrological framework that incorporates the field's random phases and finite coherence, the...

hep-phhep-exQuantum Physics

The entangling power of non-entangling channels

Julien Pinske, Jan Sperling, Klaus Mølmer·Dec 16, 2025

There are processes that cannot generate entanglement but may, nevertheless, amplify entanglement already present in a system. Here, we show that a non-entangling operation can increase the Schmidt number of a quantum state only if it can generate en...

Quantum Physicsnucl-th

Characterising the sets of quantum states with non-negative Wigner function

Nicolas J. Cerf, Ulysse Chabaud, Jack Davis +3 more·Dec 16, 2025

For Hilbert spaces $\mathcal H\subseteq L^2(\mathbb R)$ we consider the convex sets $\mathcal D_+(\mathcal H)$ of Wigner-positive states (WPS), i.e.~density matrices over $\mathcal H$ with non-negative Wigner function. We investigate the topological ...

Mathematical Physicsmath.FAQuantum Physics

Stabilizers may be poor bounds for fidelities

Aaron Z. Goldberg·Dec 16, 2025

The defining feature of ideal Gottesman-Kitaev-Preskill (GKP) states is that they are unchanged by stabilizers, which allow them to detect and correct for common errors without destroying the quantum information encoded in the states. Given this prop...

Quantum Physics

Dawn and Twilight Time in Quantum Tunneling

Tinglong Feng, Jesse Moes, Tomislav Prokopec·Dec 16, 2025

Metastable decay exhibits a familiar exponential regime bracketed by early-time deviations and late-time power-law tails. We adopt the real-time, flux-based definition of the decay rate in the spirit of Andreassen et al.\ direct method and present a ...

Quantum Physicshep-th

Testing electron-photon exchange-correlation functional performance for many-electron systems under weak and strong light-matter coupling

Iman Ahmadabadi, I-Te Lu, Leonardo A. Cunha +3 more·Dec 16, 2025

We present results of a photon-free exchange-correlation functional within the local density approximation (pxcLDA) for quantum electrodynamics density functional theory (QEDFT) that efficiently describes the electron density of many-electron systems...

Quantum Physics

Improved Lower Bounds for QAC0

Malvika Raj Joshi, Avishay Tal, Francisca Vasconcelos +1 more·Dec 16, 2025

In this work, we prove the strongest known lower bounds for QAC$^0$, allowing polynomially many gates and ancillae. Our main results show that: (1) Depth-3 QAC$^0$ circuits cannot compute PARITY, and require $Ω(\exp(\sqrt{n}))$ gates to compute MAJOR...

Quantum PhysicsComplexity

Localization from Infinitesimal Kinetic Grading: Finite-size Scaling, Kibble-Zurek Dynamics and Applications in Sensing

Argha Debnath, Ayan Sahoo, Debraj Rakshit·Dec 16, 2025

We study a one-dimensional lattice model with site-dependent nearest-neighbor hopping amplitudes that follow a power-law profile. The hopping variation is controlled by a grading exponent, $|alpha|$, which serves as the tuning parameter of the system...

cond-mat.quant-gasQuantum Physics

Sequential realization of Quantum Instruments

Soham Sau, Michal Sedlák·Dec 16, 2025

In adaptive quantum circuits classical results of mid-circuit measurements determine the upcoming gates. This allows POVMs, quantum channels or more generally quantum instruments to be implemented sequentially, so that fewer qubits need to be used at...

Quantum Physics

Microwave control of photonic spin Hall effect in atomic system

Muhammad Waseem·Dec 16, 2025

The photonic Spin Hall Effect (SHE) causes a polarization-dependent transverse shift of light at an interface. There is a significant research interest in controlling and enhancing the photonic SHE. In this paper, we theoretically investigate the mic...

physics.opticsAtomic PhysicsQuantum Physics

Reading Qubits with Sequential Weak Measurements: Limits of Information Extraction

Cesar Lema, Aleix Bou-Comas, Atithi Acharya +2 more·Dec 16, 2025

Quantum information processing and computation requires high accuracy qubit configuration readout. In many practical schemes, the initial qubit configuration has to be inferred from readout that is a time-dependent weak measurement record. However, a...

Quantum Physicscond-mat.stat-mech

Exploiting Reset Operations in Cloud-based Quantum Computers to Run Quantum Circuits for Free

Jakub Szefer·Dec 16, 2025

This work presents the first thorough exploration of how reset operations in cloud-based quantum computers could be exploited to run quantum circuits for free. This forms a new type of attack on the economics of cloud-based quantum computers. All maj...

Quantum PhysicsCryptography

Entanglement measure for the W-class states

Reza Hamzehofi·Dec 16, 2025

The structure and quantification of entanglement in the W-class states are investigated under physically motivated transformations that induce mixed-state dynamics. A rigorous condition is established linking global separability to the behavior of pa...

Quantum Physics

Fair sampling of ground-state configurations using hybrid quantum-classical MCMC algorithms

Yuichiro Nakano, Keisuke Fujii·Dec 16, 2025

We study the fair sampling properties of hybrid quantum-classical Markov chain Monte Carlo (MCMC) algorithms for combinatorial optimization problems with degenerate ground states. While quantum optimization heuristics such as quantum annealing and th...

Quantum Physics

Physics-Informed Neural Networks with Adaptive Constraints for Multi-Qubit Quantum Tomography

Changchun Feng, Laifa Tao, Lin Chen·Dec 16, 2025

Quantum state tomography (QST) faces exponential measurement requirements and noise sensitivity in multi-qubit systems, bottlenecking practical quantum technologies. We present a physics-informed neural network (PINN) framework integrating quantum me...

Quantum Physics

A Graph-Based Forensic Framework for Inferring Hardware Noise of Cloud Quantum Backend

Subrata Das, Archisman Ghosh, Swaroop Ghosh·Dec 16, 2025

Cloud quantum platforms give users access to many backends with different qubit technologies, coupling layouts, and noise levels. The execution of a circuit, however, depends on internal allocation and routing policies that are not observable to the ...

Quantum PhysicsEmerging Tech
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