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

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33,592 papers found

Boundary quenches in (1+1)-dimensional conformal field theory

Michele Fossati, Colin Rylands, Eytan Grosfeld +2 more·Jul 21, 2026

We investigate a class of local quantum quenches in which the conformal boundary condition of a (1+1)-dimensional conformal field theory is abruptly changed. We derive a remarkably simple and universal expression for the time evolution of one-point f...

cond-mat.stat-mechcond-mat.str-elhep-thQuantum Physics

Dimension Reduction for Quantum Adaptive Agents

Rishi Sundar, Thomas J. Elliott·Jul 21, 2026

Adaptive agents realise complex reactive behaviours by using a memory of past input stimuli and output actions to guide structured future responses. Quantum adaptive agents can operate while storing less information in memory than optimal classical c...

Quantum Physicscond-mat.stat-mech

Nonlinear Response via Sublinear Optics

Mykhaylo Khoma, Valeriia Bilokon, Elvira Bilokon +1 more·Jul 21, 2026

Sublinear optical response, in which the emitted field scales as a fractional power of the driving field, lies beyond the conventional perturbative hierarchy of nonlinear optics. Here, we show that such a response can be engineered in a hydrogen atom...

Quantum Physics

Quantum Circuits for Quantum Spatial Search on $d$-Dimensional Lattices

Rei Sato·Jul 21, 2026

We propose an explicit quantum circuit for quantum spatial search based on discrete-time quantum walks on $d$-dimensional lattices. In this algorithm, the flip-flop shift operator moves the walker to a neighboring site along the selected spatial dire...

Quantum Physics

The arrow of time, irreversibility, equilibrium and measurement in quantum mechanics

Christopher J. N. Coveney, Peter V. Coveney·Jul 21, 2026

Quantum mechanics is widely recognised as being incomplete. It is not consistent with the second law of thermodynamics and does not provide a scientifically credible physical account of the measurement process, the means by which coherence is broken ...

Quantum Physicscond-mat.stat-mechMathematical Physicsphysics.hist-ph

Quantum limits to chiroptical molecular discrimination

Mikael P. Backlund·Jul 21, 2026

Discriminating enantiomer pairs is of central importance in the molecular sciences. The preferential interaction between chiral light and matter is commonly employed in this discrimination, despite fundamental challenges. Here we present quantitative...

Quantum Physicsphysics.chem-phphysics.optics

Single Link Removal Perturbation in Szegedy Quantum Walk: from Graph Completeness Testing to Integrity Monitoring

Sara Giordano, Miguel A. Martin-Delgado·Jul 21, 2026

We present a rigorous perturbative analysis of the Szegedy quantum walk search algorithm on the complete graph with marked nodes, when a specific anomaly is present in the graph. This is motivated by the problem of monitoring the integrity of dense t...

Quantum Physics

Quasi-Non-Hermitian Edge Bursts Induced by Nonuniform Loss

Ze Yang, Wei Li, Fuxiang Li·Jul 21, 2026

Non-Hermitian quantum walks on lossy lattices with open boundaries can exhibit an anomalous peak of the loss probability at the boundary, known as the non-Hermitian edge burst (NHEB). This phenomenon has been attributed to the combined effect of the ...

Quantum Physics

Lower Bounds on Spectral Gaps of Parent Hamiltonians via Tensor Networks

Milán Ádám Rozmán, András Molnár, Norbert Schuch·Jul 21, 2026

Proving spectral gaps above the ground space is a central problem in quantum many-body physics. Yet, finding lower bounds on the gap is notoriously difficult. We revisit the martingale method, originally developed by Fannes, Nachtergaele, and Werner ...

Quantum Physicscond-mat.str-el

How to improve the discrimination power of classically simulable measurements?

Yiran Wang, Yongming Li·Jul 21, 2026

Classically simulable measurements (CSMs) constitute an important class of restricted measurements in the odd-prime-dimensional magic resource theory, referring to those measurements with positive discrete Wigner functions. Since their discrimination...

Quantum PhysicsMathematical Physics

Secure OFDM-IM ISAC With Artificial-Noise-Aided Index Deception

Ufuk Altun, Onur Günlü·Jul 21, 2026

We propose an artificial noise (AN)-aided, secure OFDM with index modulation (OFDM-IM) framework for integrated sensing and communication (ISAC). Consider a security-critical scenario, where the sensing target is also a potential eavesdropper. Instea...

cs.ITEmerging Tech

Metric completion of the Bender--Brody--Müller Hamiltonian: dilation spectrum and missing eigenstates

Kejun Liu·Jul 21, 2026

The Bender--Brody--Müller (BBM) Hamiltonian was proposed as a non-Hermitian Hilbert--Pólya operator. We analyze the Hilbert completion induced, on the standard half-line $L^2$ core, by BBM's candidate metric $\hatη=\sin^2(\hat p/2)=Δ^\daggerΔ/4$. The...

Mathematical Physicsmath.SPQuantum Physics

On the completeness of transformation rules in reversible logic synthesis

Shiguang Feng, Zongxing Xiong, Lvzhou Li·Jul 21, 2026

Transformation rules play a central role in reversible circuit optimization, template-based rewriting, and equivalence checking, and establishing their completeness is a fundamental problem in reversible logic synthesis. In this work, we investigate ...

Emerging Tech

Hardware-in-the-Loop Syndrome-to-Decoder Validation for Repetition, Surface, CSS-LDPC, and Digitized-GKP Codes

Dennis Delali Kwesi Wayo, Chinonso Onah, Rodrigo Alves Dias +2 more·Jul 21, 2026

Quantum error-correction experiments increasingly require a verified interface between measured syndrome bits and decoder-native correction requests. We report a four-branch syndrome-to-decoder study spanning three IBM gate-model hardware circuits an...

Quantum Physics

Bound Entanglement Is Insufficient for an Exponential Quantum Learning Advantage

Hyeongu Kang, Sangwoo Jeon, Changhun Oh·Jul 21, 2026

While entanglement is known to enable exponential improvements in the sample complexity of quantum learning, it remains unclear which properties of entangled resources are responsible for such improvements. We address this question through the reduct...

Quantum Physics

Decoder Comparability Across Quantum Software Stacks: Repeated-Round Surface and Digitized-GKP Syndrome Replay

Dennis Delali Kwesi Wayo, Chinonso Onah, Rodrigo Alves Dias +2 more·Jul 21, 2026

We present a contract-preserving, family-aware comparison of decoder behavior across four syndrome-generation stacks (PennyLane, Qiskit, Cirq, and a LiDMaS+ reference) under a fixed replay interface. Request streams from repeated-round surface-code a...

Quantum Physics

Bayesian Sequential Quantum Amplitude Estimation for Rare-Event Structural Failure Probability

Alireza Tabarraei·Jul 21, 2026

Structural reliability analysis often requires estimating small failure probabilities under uncertainty, a task for which direct Monte Carlo simulation becomes inefficient because failure observations are scarce. Quantum amplitude estimation offers a...

Emerging Techmath.NT

Sixteen-State Energy Mapping for First-Principles Four-Spin Ring Exchange: Validation on $La_2CuO_4$ and $SrFeO_2$

Xavier Rocquefelte, Peter Blaha·Jul 21, 2026

Four-spin ring (cyclic) exchange $J_{ring}$ is an essential ingredient of the Heisenberg spin Hamiltonian of cuprates and other square-lattice magnets, yet it has lacked the kind of direct, local first-principles extraction that the four-state method...

cond-mat.mtrl-scicond-mat.str-elQuantum Physics

Coherent-disorder-driven complexity transitions in a quantum-advantage architecture

Sung-Bin B. Lee, Chae-Yeun Park, Changhun Oh +1 more·Jul 21, 2026

While decoherence is known to erode classical hardness in quantum random sampling, the impact of coherent spatial disorder remains an open question. We study a square-lattice instantaneous quantum polynomial-time (IQP) architecture subject to two-qub...

Quantum Physics

Collective Coherent Perfect Absorption in a Synthetic Photon-Phonon Lattice

Sihan Wang, Qichun Liu, Bo Song +3 more·Jul 21, 2026

Coherent perfect absorption (CPA) has emerged as a powerful paradigm for controlling classical and quantum light, and has been demonstrated across a broad range of physical platforms. CPA realized in optomechanics relies on interference between the i...

Quantum Physics
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