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Papers

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

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12,891 papers in 12 months (-5% vs prior quarter)

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27,548 papers found

Butterfly Echo Protocol for Axis-Agnostic Heisenberg-Limited Metrology

Jacob Bringewatt, Leon Zaporski, Matthew Radzihovsky +4 more·Feb 26, 2026

The extreme sensitivity of chaotic systems to external perturbations makes them natural candidates for sensing applications. We propose a single-shot echo-based protocol for estimating small rotations about an unknown axis that leverages random symme...

Quantum Physics

Analogue many-body gravitating quantum systems with a network of dipolar Bose-Einstein condensates

Youssef Trifa, Dario Cafasso, Marco Fattori +1 more·Feb 26, 2026

Operational probes of the interface between quantum mechanics and general relativity in the Newtonian regime -- via mass-energy equivalence in clocks or spatial superpositions in interferometers -- share a common description in terms of an effective ...

Quantum Physicscond-mat.quant-gasgr-qc

Copy-cup Gates in Tensor Products of Group Algebra Codes

Ryan Tiew, Nikolas P. Breuckmann·Feb 26, 2026

We determine conditions on classical group algebra codes so that they have pre-orientation for cup products and copy-cup gates. This defines quantum codes that have constant-depth $\operatorname{CZ}$ and $\operatorname{CCZ}$ gates constructed via ten...

Quantum Physics

Efficient evaluation of fundamental sensitivity limits and full counting statistics for continuously monitored Gaussian quantum systems

Francesco Albarelli, Marco G. Genoni·Feb 26, 2026

Generalized master equations (GMEs) -- time-local but generally neither trace-preserving nor Hermiticity-preserving -- are convenient tools to compute properties of the environment of an open or continuously monitored quantum system. A two-sided mast...

Quantum Physics

Quantum Confocal Microscopy in Fock Space with a 19 dB Metrological Gain

Ziyue Hua, Chuanlong Ma, Yilong Zhou +12 more·Feb 26, 2026

Quantum metrology promises measurement precision beyond classical limits by exploiting large-scale quantum states, yet realizing this advantage faces two fundamental challenges: the deterministic preparation of non-trivial quantum probes and the effi...

Quantum Physics

Gaussian mode coupling of spectrally broadband photons from bulk spontaneous parametric down-conversion: A spatial-spectral mode analysis of fiber coupling

Carlos Sevilla-Gutiérrez, Varun Raj Kaipalath, Fabian Steinlechner·Feb 26, 2026

Photon sources based on spontaneous parametric down-conversion (SPDC) are central to experimental quantum optics and quantum technologies. Their performance is commonly quantified by three metrics: pair-collection probability, heralding efficiency, a...

Quantum Physics

Polarization-selective quantum cooperative response in dual-species atom arrays

Huan Wang, Shangguo Zhu, Yun Long +4 more·Feb 26, 2026

Atom arrays have emerged as a powerful platform for quantum light-matter interfaces, yet single-species arrays are constrained by in-plane symmetry, restricting polarization control. Here we investigate the cooperative optical response of dual-specie...

Quantum Physicscond-mat.quant-gasAtomic Physicsphysics.optics

Quantum diffusion for a quantum particle with a correlated Gaussian noise

Yun Jeong Kang, Sung Kyu Seo, Kyungsik Kim·Feb 26, 2026

We investigate the diffusive behavior of a quantum particle driven by a correlated Gaussian noise. We derive the analytical solution of the joint probability density function and obtain explicit expressions for the mean square momentum and the mean s...

Quantum Physicscond-mat.stat-mech

Connecting Quantum Contextuality and Nonlocality

Jianqi Sheng, Dongkai Zhang, Lixiang Chen·Feb 26, 2026

Quantum theory departs from classical physics in its treatment of correlations, most prominently through the phenomena of contextuality and nonlocality. Once regarded primarily as foundational curiosities, these effects are now understood as key oper...

Quantum PhysicsMathematical Physicsphysics.optics

Scaling and Luescher Term in a non-Abelian (2+1)d SU$(2)$ Quantum Link Model

Paul Ludwig, Timo Jakobs, Carsten Urbach·Feb 26, 2026

We investigate a non-Abelian SU$(2)$ quantum link model in $2+1$ dimensions on a hexagonal lattice using tensor network methods. We determine the static quark potential for a wide range of bare coupling values and find that the theory is confining. W...

hep-latQuantum Physics

Dequantization Barriers for Guided Stoquastic Hamiltonians

Yassine Hamoudi, Yvan Le Borgne, Shrinidhi Teganahally Sridhara·Feb 26, 2026

We construct a probability distribution, induced by the Perron--Frobenius eigenvector of an exponentially large graph, which cannot be efficiently sampled by any classical algorithm, even when provided with the best-possible warm-start distribution. ...

Quantum PhysicsComplexityData Structures

Excited-state quantum phase transitions and chaos in a three-level Lipkin model

Alberto Mayorgas, Pedro Pérez-Fernández, Álvaro Sáiz +1 more·Feb 26, 2026

Excited-state quantum phase transitions (ESQPTs) have been extensively studied in two-level models, but their characterization remains challenging in systems displaying mixed regular and chaotic dynamics. In this work, we investigate ESQPTs within th...

Quantum PhysicsMathematical Physics

Quantum Deep Learning: A Comprehensive Review

Yanjun Ji, Zhao-Yun Chen, Marco Roth +10 more·Feb 26, 2026

Quantum deep learning (QDL) explores the use of both quantum and quantum-inspired resources to determine when deep learning's core capabilities, such as expressivity, generalization, and scalability, can be enhanced based on specific resource constra...

Quantum Physicscs.LG

A Maxwell Fish-Eye Lens in a Bose-Einstein Condensate

Jelte Duchêne, Elinor Kath, Floriane Arrouas +7 more·Feb 26, 2026

We experimentally realize an analogue of the optical Maxwell fish-eye lens (MFEL) using phononic excitations in a Bose-Einstein condensate (BEC). A MFEL is characterized by a radially symmetric, spatially varying refractive index with the remarkable ...

cond-mat.quant-gasAtomic Physicsphysics.opticsQuantum Physics

Thermodynamic uncertainty relation under continuous measurement and feedback with quantum-classical-transfer entropy

Kaito Tojo, Takahiro Sagawa, Ken Funo·Feb 26, 2026

We derive a thermodynamic uncertainty relation (TUR) under quantum continuous measurement and feedback control. By incorporating the quantum-classical-transfer entropy, which quantifies the information gained by continuous measurement, we show that t...

cond-mat.stat-mechQuantum Physics

Coupling-energy driven pumping through quantum dots: the role of coherences

Lukas Litzba, Gernot Schaller, Jürgen König +1 more·Feb 26, 2026

We study the impact of off-resonant tunneling and coherences on the electron pumping through quantum dots. Thereby, we focus on two electron-pump setups where lowest-order tunneling processes are suppressed and the pump is exclusively driven by modul...

Mesoscale PhysicsQuantum Physics

Q-Tag: Watermarking Quantum Circuit Generative Models

Yang Yang, Yuzhu Long, Han Fang +4 more·Feb 26, 2026

Quantum cloud platforms have become the most widely adopted and mainstream approach for accessing quantum computing resources, due to the scarcity and operational complexity of quantum hardware. In this service-oriented paradigm, quantum circuits, wh...

Quantum Physicscs.LG

Geometric control of maximal entanglement via bound states in the continuum

Alexis R. Legón, Mario Miranda Rojas, Pedro Orellana +1 more·Feb 26, 2026

Bound states in the continuum (BiCs) convert dissipative open systems into effectively closed quantum subspaces through destructive interference. We show that two identical giant atoms coupled to a one-dimensional waveguide support BICs that coincide...

Quantum Physics

Long Range Frequency Tuning for QML

Michael Poppel, Jonas Stein, Sebastian Wölckert +2 more·Feb 26, 2026

Quantum machine learning models using angle encoding naturally represent truncated Fourier series, providing universal function approximation capabilities with sufficient circuit depth. For unary fixed-frequency encodings, circuit depth scales as O(o...

cs.LGAIEmerging TechQuantum Physics

Cryptographic Fragility of Standard Quantum Repeater Protocols

Abhishek Sadhu, Sharu Theresa Jose·Feb 26, 2026

The security of the proposed quantum Internet relies on repeater protocols designed under the assumption of stochastic, characterizable noise. We demonstrate that in adversarial environments this assumption induces performance vulnerabilities for com...

Quantum Physics
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