Quantum Computing
Quantum Computing news — Monday 02 November 2026
147 stories from 3 sources, every one in English. Each links to its publisher.
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Alice ＆ Bob Demonstrates Multi-Hour Physical Bit-Flip Suppression on Single-Cat and Helium 2 Processors
Quantum Computing Report
Alice & Bob has achieved a significant breakthrough in quantum computing, demonstrating macroscopic bit-flip lifetimes exceeding one hour on their bosonic cat-qubit hardware. Their single-qubit device showed an average idle bit-flip…
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Qtonic Quantum Appoints Former NATO Commander as Head of Operations
The Quantum Insider
Insider Brief Qtonic Quantum has appointed retired U.S. Army Lt. Gen. Roger L. Cloutier Jr., former commander of NATO Allied Land Command, to lead the company’s operations. Cloutier will oversee the company’s organizational structure and…
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FAU Researchers Test Quantum Machine Learning for Lung Cancer Prediction
The Quantum Insider
Insider Brief Florida Atlantic University researchers evaluated quantum machine learning methods for lung cancer prediction using a limited dataset of symptoms and risk factors. A D-Wave quantum annealing-based support vector machine…
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How Many Qubits Would it Take to Simulate a Holographic Universe?
The Quantum Insider
Insider brief In the latest episode of The Quantum Kid, theoretical physicist Juan Maldacena of the Institute for Advanced Study explains the holographic principle. This is the idea that everything inside a region of space, gravity…
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HKUST and HKMA Launch PQC Toolkit for Banks
The Quantum Insider
Insider Brief The Hong Kong University of Science and Technology (HKUST) and the Hong Kong Monetary Authority (HKMA) have launched a Post-Quantum Cryptography (PQC) Toolkit to help banks plan their transition to quantum-safe cryptography…
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South Korea Launches Hangang Supercomputer, Plans Quantum Integration
The Quantum Insider
Insider Brief South Korea has brought Hangang, its sixth national supercomputer, into full operation, with the government expecting it to rank among the world’s top 10 systems. Hangang has 8,496 GPUs and 9,936 CPUs, delivering 24 times the…
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Scottish Widows Targets Quantum Computing With UK Venture Growth Investments
The Quantum Insider
Insider Brief Scottish Widows is directing workplace pension savings into U.K. technology businesses, with Oxford Quantum Circuits and Quantum Motion among its expected initial investments. Aberdeen Investments appointed IP Group to…
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Nobel Laureate John Martinis to Deliver Quantum Computing Lecture at UWA
The Quantum Insider
Insider Brief Nobel Laureate Professor John Martinis will deliver a free public lecture at the University of Western Australia (UWA) on the development of quantum computing and the experiments behind superconducting qubits. Martinis, who…
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Quantcore Welcomes Innovation Minister to Showcase Manufacturing Ambitions
The Quantum Insider
Insider Brief Scottish innovation minister Alyn Smith visited Quantcore to discuss government support for Scotland’s quantum manufacturing sector and tour its superconducting quantum hardware labs. A roundtable with Quantcore and…
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Equal1 Appoints Andrew Flynn as Chief Operating Officer
The Quantum Insider
Insider Brief Equal1 has appointed Andrew Flynn as Chief Operating Officer to lead operations as the company scales commercialisation of its RacQ rack-mounted quantum computer. Flynn brings more than 20 years of experience in semiconductor…
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Chattanooga Accelerator Selects Four Quantum Startups For Commercialization Program
The Quantum Insider
Insider Brief Chattanooga’s CO.LAB selected four quantum startups for a 12-month commercialization program connecting them with technical resources, prospective customers and pilot opportunities. The inaugural cohort includes Ridge…
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BTQ Technologies Brings MIMIQ Quantum Emulator to qBraid
The Quantum Insider
Insider Brief BTQ Technologies’ MIMIQ quantum emulator, developed by subsidiary QPerfect, is now available through qBraid’s managed API, giving its developer community access to large-scale quantum emulation. MIMIQ combines state-vector…
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IDEMIA Secure Transactions Receives EMVCo Certification for PQC Payment Cards
The Quantum Insider
Insider Brief IDEMIA Secure Transactions (IST) received EMVCo certification for a Java Card platform that combines post-quantum cryptography (PQC) and crypto-agility capabilities. The platform includes an IST-designed secure chip with a…
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Adelaide Researchers Develop Simpler Design for Highly Sensitive Quantum Sensors
The Quantum Insider
Insider Brief Adelaide University researchers developed and experimentally demonstrated a superconducting sensor design that identifies zero magnetic field while preserving conditions needed for maximum sensitivity. The approach…
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Reaffirming a Challenge to Bohmian Mechanics
arXiv quant-ph
arXiv:2509.06584v5 Announce Type: replace Abstract: In our work [Sharoglazova et al., Nature 643, 67-72 (2025)], we reported the first measurement of the speed of tunnelling particles by comparing two orthogonal motions in a…
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A Diagrammatic Method for Non-Gaussian Photon Correlations in Weakly Coupled Atomic Ensembles
arXiv quant-ph
arXiv:2509.03970v3 Announce Type: replace Abstract: We develop a scattering-theory formalism and use it to predict that a resonantly driven atomic ensemble weakly coupled to an optical mode can generate light with non-Gaussian…
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Universal resources for quantum approximate optimization algorithm and quantum annealing
arXiv quant-ph
arXiv:2506.03241v3 Announce Type: replace Abstract: The Quantum Approximate Optimization Algorithm (QAOA) is a variational ansatz that resembles the Trotterized dynamics of a Quantum Annealing (QA) protocol. This work formalizes this…
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Improved Algorithms for Quantum MaxCut via Partially Entangled Matchings
arXiv quant-ph
arXiv:2504.15276v2 Announce Type: replace Abstract: We introduce a $0.611$-approximation algorithm for Quantum MaxCut and a $\frac{1+\sqrt{5}}{4} \approx 0.809$-approximation algorithm for the EPR Hamiltonian of [arXiv:2209.02589]. A novel…
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Certification of quantum correlations at arbitrary distances through routed Bell tests
arXiv quant-ph
arXiv:2502.12241v3 Announce Type: replace Abstract: Transmission loss represents a major obstacle to the device-independent certification of quantum correlations over long distances, limiting applications such as device-independent quantum…
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Persistence of Unitary Almost Mathieu Operator Gaps Ten Dry Martinis, Five on the Rim
arXiv quant-ph
arXiv:2610.42120v1 Announce Type: cross Abstract: We determine exactly which gap labels are realized by open spectral gaps for the unitary almost Mathieu operator at every irrational frequency and all coupling constants…
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Focusing through coupled multimode fibers for miniaturized single-atom tweezer arrays
arXiv quant-ph
arXiv:2610.41917v1 Announce Type: cross Abstract: Real-world deployment of quantum technologies requires systems in low SWaP-C packages. Quantum platforms based on ultracold atoms typically trap and control atoms with optical tweezers…
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Query-Efficient Quantum Multi-Objective Optimization for Materials Configuration Search via Bayesian Weight Selection
arXiv quant-ph
arXiv:2610.41788v1 Announce Type: cross Abstract: Materials design is a multi-objective problem, and recent advances in quantum optimization make it possible to bring quantum solvers to bear on such problems. The realistic near-term win…
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A Hybrid Message-Passing and Electric-Field Representation for Electrostatic QM/MM Embedding with Machine Learning Interatomic Potentials
arXiv quant-ph
arXiv:2610.41523v1 Announce Type: cross Abstract: Within a hybrid quantum mechanics/molecular mechanics approach a small region of a large atomistic system is described quantum mechanically, while the rest of the system is represented by a…
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Quantum Popcorn: the shape of a phase transition bubble
arXiv quant-ph
arXiv:2610.41504v1 Announce Type: cross Abstract: A quantum tunneling event in field theory is usually depicted as the materialization of a spherical bubble of true vacuum. The bubble appears at rest, and its profile is the time-symmetric…
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Tunable Three-Body Interactions in Microwave-Shielded Polar Molecules
arXiv quant-ph
arXiv:2610.41003v1 Announce Type: cross Abstract: We show that microwave shielding, which enables collisionally stable ultracold polar molecules, also leads to genuine nonadditive three-body interactions comparable to the shielding…
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Characteristics of VHF and UHF band detection using Stark shifting in Rydberg-atom sensors
arXiv quant-ph
arXiv:2610.40952v1 Announce Type: cross Abstract: We present a characterization of the sensitivity of broadband electric field measurements in the Very High Frequency (VHF) and Ultra High Frequency (UHF) bands using AC stark shifting of…
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Benchmarking One-Dimensional Quantum Lattice Boltzmann Methods on Quantum Hardware
arXiv quant-ph
arXiv:2610.40851v1 Announce Type: cross Abstract: Classical computational fluid dynamics (CFD) methods encounter significant computational bottlenecks in large systems and at high Reynolds number flows due to the rapid increase in degrees…
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Relating approaches to interacting quantum clocks and systems
arXiv quant-ph
arXiv:2610.40791v1 Announce Type: cross Abstract: The problem of describing the dynamics of quantum systems relative to quantum clocks with which they interact is relevant to the physics of quantum reference frames and quantum gravity…
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Gapless and Non-Equilibrium Topology in Blockaded Ladders
arXiv quant-ph
arXiv:2610.40771v1 Announce Type: cross Abstract: We propose a multi-leg PXYP model as a minimal setting to explore constraint-induced intertwinement between itinerant and internal degrees of freedom. We argue that the Rydberg-like…
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Time-optimal quantum dynamics under fixed-norm generators
arXiv quant-ph
arXiv:2610.42131v1 Announce Type: new Abstract: We investigate the dynamics of quantum systems whose evolution is governed by linear generators of fixed unitarily invariant norm. For this broad class of evolutions, we derive a universal…
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Topologically Protected Edge States in a Single Flux Qubit
arXiv quant-ph
arXiv:2610.42114v1 Announce Type: new Abstract: We show that topological edge states can be realized in a simple superconducting circuit composed of an inductively shunted flux qubit. The Josephson potential of that qubit forms a honeycomb…
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Logical Bell Inequalities for Marginal Wigner Negativity
arXiv quant-ph
arXiv:2610.42017v1 Announce Type: new Abstract: We construct logical Bell inequalities whose violations are determined by the Wigner function of a reduced quantum state. For odd-prime qudits, each phase-space point of any nonempty proper…
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Resource efficient Sample Based Quantum Simulation through Fragmentation and Virtual Partitioning of QPU
arXiv quant-ph
arXiv:2610.41986v1 Announce Type: new Abstract: Present-day sample-based quantum algorithms within quantum-centric supercomputing workflows require substantial classical post-processing, large circuit depths to produce chemically relevant…
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GENIE: learned quantum circuits as embedding impurity solvers, and why compactness, not correlation strength, decides when they work
arXiv quant-ph
arXiv:2610.41957v1 Announce Type: new Abstract: Sample-based quantum diagonalization has been used as an impurity solver in density matrix embedding theory (DMET), but always with fixed-form circuits and without comparison to classical…
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Hybrid Quantum Algorithms for Trade Surveillance Analytics
arXiv quant-ph
arXiv:2610.41874v1 Announce Type: new Abstract: Anti-money laundering (AML) and trade surveillance remain largely manual: rule-based monitoring raises alerts of which, by estimate, over 95% are false positives, each reviewed by a human…
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Toward Quantum Monte Carlo for Sovereign Debt Risk: A proof of concept
arXiv quant-ph
arXiv:2610.41831v1 Announce Type: new Abstract: We present a proof-of-concept pipeline that applies quantum amplitude estimation to the probability that a sovereign debt-to-GDP ratio exceeds a critical threshold at a given horizon. The…
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Scaling laws of entanglement entropy in fractal dimensions
arXiv quant-ph
arXiv:2610.41761v1 Announce Type: new Abstract: Entanglement entropy scaling links geometry to quantum correlations and diagnoses quantum criticality. Fractal lattices extend this link to noninteger dimensions, where boundary and bulk…
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A Highly Nondegenerate Photon-Pair Source for Detector-Matched Quantum Key Distribution
arXiv quant-ph
arXiv:2610.41709v1 Announce Type: new Abstract: In a commercial entanglement-distribution system over telecom fibre, the single-photon detectors are the largest part of the hardware cost. In entanglement-based quantum key distribution…
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Extending Sample-based Quantum Diagonalization to Systems of Linear Equations
arXiv quant-ph
arXiv:2610.41708v1 Announce Type: new Abstract: Solving systems of linear equations, $Ax=b$, is a ubiquitous task in computational science. The Harrow-Hassidim-Lloyd algorithm requires phase estimation, controlled rotations, and…
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Simulating two-Dimensional decaying vortex structure with the Carleman-Lattice-Boltzmann method
arXiv quant-ph
arXiv:2610.41653v1 Announce Type: new Abstract: We perform a numerical study of the free decay of two-dimensional nonlinear vortex structures using the second-order-truncated Carleman-Lattice Boltzmann method (CLB2). To this purpose, we…
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Quantum machine learning geospatial time-series by seasonal encoding
arXiv quant-ph
arXiv:2610.41649v1 Announce Type: new Abstract: Quantum data reuploading models can increase the expressive capacity of variational quantum models, but do not necessarily improve predictive performance. In the present work, we investigate…
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Quantum Bernstein--Kolmogorov--Arnold approximation
arXiv quant-ph
arXiv:2610.41608v1 Announce Type: new Abstract: This paper addresses the expressivity and representation gap in Quantum Neural Networks by establishing a quantum analogue of the classical Kolmogorov--Arnold representation theorem. We…
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Symmetries and model reduction in a $\cos 2\varphi$ transmon qubit
arXiv quant-ph
arXiv:2610.41542v1 Announce Type: new Abstract: Engineered symmetries in superconducting circuits can protect quantum information; much like selection rules in atomic physics, they forbid transitions between the qubit states. Protected…
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eCAS: An Orbital Embedding Method for Quantum Computing
arXiv quant-ph
arXiv:2610.41517v1 Announce Type: new Abstract: Future fault-tolerant quantum computers will allow us to calculate electronic structures of atomistic systems. However, these systems will be intrinsically limited in size, requiring…
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Real-time BP decoding of a high-rate QEC code
arXiv quant-ph
arXiv:2610.41413v1 Announce Type: new Abstract: We present a real-time FPGA decoder for a high-rate $[[512,174,8]]$ 3D product qLDPC code. We construct a circuit-level detector-error model for a compact syndrome-extraction schedule and…
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Loss-aware optimization of realistic GKP gid states
arXiv quant-ph
arXiv:2610.41388v1 Announce Type: new Abstract: Realistic preparation of Gottesman-Kitaev-Preskill (GKP) states, the prime candidates for quantum computation with bosonic systems, is inevitably burdened by photon loss. We show how taking…
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PyQLAS: A Quantum-Classical Hybrid Solver Library for Linear Systems
arXiv quant-ph
arXiv:2610.41317v1 Announce Type: new Abstract: Quantum algorithms solve a linear system at a cost that grows only polylogarithmically in its dimension, but on present-day hardware that advantage is realised only if the quantum and the…
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Optimality of the Petz-Fuchs Smoothed State
arXiv quant-ph
arXiv:2610.41311v1 Announce Type: new Abstract: Quantum state smoothing is an estimation technique that uses past and future measurement information obtained from a continuous-in-time measurement record to reconstruct the state of an open…
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Testing hardware quantum machine learning claims with a null circuit: fill prediction on Binance futures with 129 qubits of an IBM Heron processor
arXiv quant-ph
arXiv:2610.41268v1 Announce Type: new Abstract: Quantum processors are now used as feature generators for classical models on tabular data. A circuit encodes each record, the device returns expectation values, and a classical model learns…
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Quantum Advantage in Beam-Displacement Estimation for Inter-Satellite Quantum-Secure Time Transfer
arXiv quant-ph
arXiv:2610.41198v1 Announce Type: new Abstract: In this work, we investigate the practical feasibility of achieving a quantum advantage, in the context of inter-satellite quantum communication, of satellite position estimation. The…
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Encoded reversible addition in constant Toffoli depth
arXiv quant-ph
arXiv:2610.41142v1 Announce Type: new Abstract: We show that reversible in-place quantum addition modulo $2^n-1$ can be implemented in constant Toffoli depth using $O(n)$ space, provided that the variables are encoded in a certain…
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Probing Operator Spreading with Local Quantum Fluctuations
arXiv quant-ph
arXiv:2610.41140v1 Announce Type: new Abstract: Measuring out-of-time-ordered correlators (OTOCs) is experimentally challenging, often requiring effective reversal of many-body dynamics. Here, we propose an alternative approach to probing…
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Entangled Measurement Outcomes for Optimal Postselection in Quantum Batteries
arXiv quant-ph
arXiv:2610.41121v1 Announce Type: new Abstract: Postselection can enhance the performance of a selected quantum battery branch, raising the question of whether the optimum can always be achieved by product measurements on the auxiliary…
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Preparation of a Laughlin-like fractional Chern insulator on a superconducting quantum processor
arXiv quant-ph
arXiv:2610.41017v1 Announce Type: new Abstract: Fractional Chern insulators (FCIs) are lattice analogues of fractional quantum Hall states, hosting topological order and fractionalized anyonic excitations. Their realization poses a…
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Hypergraph cycle enumeration for efficient inference of planted k-XOR with smooth trade-off
arXiv quant-ph
arXiv:2610.40941v1 Announce Type: new Abstract: We introduce hypergraph cycle enumeration (HCE), a simple spectral framework for detecting and recovering planted signals in noisy hypergraph inference problems. We study HCE on one…
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Colloquium: Quantum information processing with ensembles of identical particles
arXiv quant-ph
arXiv:2610.40852v1 Announce Type: new Abstract: Identical particles underpin most quantum technologies, but the role of indistinguishability in these processes extends far beyond the symmetrization of many-particle states. This Colloquium…
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Witnessing and quantifying stellar rank with the Wigner function
arXiv quant-ph
arXiv:2610.40827v1 Announce Type: new Abstract: Quantifying non-Gaussianity is essential for assessing the computational power of bosonic quantum systems. We introduce a framework to witness and quantify non-Gaussianity from displaced…
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Beyond the Kubo formula: unification of adiabatic and isothermal response in quantum systems
arXiv quant-ph
arXiv:2610.40810v1 Announce Type: new Abstract: The static limit of the Kubo susceptibility describes the adiabatic response of an isolated quantum system, in which energy-level occupations remain unchanged, and generally differs from the…
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Liouvillian spectral snapshots: A reduced-subspace approach for time-dependent and noisy open quantum systems
arXiv quant-ph
arXiv:2610.40808v1 Announce Type: new Abstract: Driven-dissipative quantum devices are routinely operated with time-dependent drives and exposed to temporally correlated classical noise. When these perturbations vary on timescales…
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Quantum manifestations of converse symmetry breaking
arXiv quant-ph
arXiv:2610.40762v1 Announce Type: new Abstract: Quantum synchronization holds promise in advancing quantum technologies such as sensing, communication, and computation. A key challenge in this rapidly developing field is to identify…
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Finite-resource cooling of qudits beyond thermodynamic length
arXiv quant-ph
arXiv:2610.40709v1 Announce Type: new Abstract: Cooling a quantum system with $N$ thermal machines costs more than Landauer's bound. For swap-based collision models the excess is set by thermodynamic length, which is optimal for qubits and…
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SeQUeNCe.DQC: Full-stack Simulation of Distributed Quantum Computing
arXiv quant-ph
arXiv:2610.39476v2 Announce Type: replace-cross Abstract: Distributed quantum computing (DQC) connects multiple quantum processing units to overcome the scale limits of monolithic hardware. We introduce SeQUeNCe$.$DQC a new top-level…
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A Primer on Instanton Physics - A Short Course
arXiv quant-ph
arXiv:2610.38717v2 Announce Type: replace-cross Abstract: These six lectures, delivered at the University of New Brunswick 6-21 October 2026, are an introduction to instantons in quantum mechanics and quantum field theory for senior…
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The Floquet-Magnus expansion of unbounded operators
arXiv quant-ph
arXiv:2605.23734v2 Announce Type: replace-cross Abstract: The Floquet-Magnus expansion is a widely used tool to derive effective descriptions of time-periodic quantum systems by approximating their dynamics with a time-independent…
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Symmetry breaking transforms strong to normal correlation and false metals to true insulators
arXiv quant-ph
arXiv:2512.18236v4 Announce Type: replace-cross Abstract: Material scientists and condensed matter physicists have long been divided on the issue of choosing the conceptual framework for explaining why open-shell transition-metal oxides…
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Resonant analogue configurations in atomic condensates
arXiv quant-ph
arXiv:2406.10027v2 Announce Type: replace-cross Abstract: As a contribution to a memorial volume, we provide a comprehensive discussion of resonant configurations in analogue gravity, focusing on its implementation in atomic condensates…
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Cross-Platform Verification of Continuous-Variable Quantum Systems
arXiv quant-ph
arXiv:2610.39912v2 Announce Type: replace Abstract: Cross-platform verification compares output states of independently operated bosonic and quantum optical systems when classical predictions and joint measurements are unavailable…
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Schur--Weyl Reduction of Finite-Copy Precision Bounds for Multiparameter Quantum Estimation
arXiv quant-ph
arXiv:2610.38299v2 Announce Type: replace Abstract: In multiparameter quantum estimation, incompatible measurements can impose trade-offs among estimation errors. Understanding the precision attainable with a finite number of jointly…
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Sample Complexity for Generative Learning of Quantum Measurement Data
arXiv quant-ph
arXiv:2610.38028v2 Announce Type: replace Abstract: Generative learning of a quantum measurement distribution from finite data requires choosing a model capacity that balances representation accuracy against estimation cost. We develop a…
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Reducing the cost of ancilla purification for Majorana quantum computation
arXiv quant-ph
arXiv:2610.37991v2 Announce Type: replace Abstract: Braiding Majorana zero modes does not by itself provide a universal set of quantum gates. Additional operations can be supplied through ancillary states, whose preparation need not have…
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Non-Clifford quantum cellular automata from invertible topological quantum field theories
arXiv quant-ph
arXiv:2607.21697v2 Announce Type: replace Abstract: Quantum cellular automata (QCAs) describe locality-preserving quantum dynamics and link quantum information, many-body physics, and topological quantum field theory (TQFT). Constructing a…
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An analytical solution of a quantum system with non-Markovian behavior: The Bixon-Jortner system in time domain
arXiv quant-ph
arXiv:2607.07546v2 Announce Type: replace Abstract: Non-Markovian behavior in quantum systems is often studied in the context of bipartite systems consisting of a system of interest and an environment -- tracing over the environment…
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Non-Hermiticity of an anomalous superradiant phase
arXiv quant-ph
arXiv:2606.26770v2 Announce Type: replace Abstract: We present a Hermitian squeezing-Dicke model as a minimal closed-system setting for non-Hermitian many-body physics. Squeezing generates an effective parity-time ($\mathcal{PT}$) symmetry…
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Interpretable Machine Learning for Building Analytic Quantum Circuits: the Case of Diagonal Operators
arXiv quant-ph
arXiv:2605.06633v4 Announce Type: replace Abstract: Machine Learning has become a useful instrument across many fields, but the opacity of typical ``black-box'' models limits their value for scientific discovery. In this paper we present a…
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Graph-theory measures capture weak ergodicity breaking on large quantum systems
arXiv quant-ph
arXiv:2605.00094v3 Announce Type: replace Abstract: We study the onset of weak ergodicity violations in closed quantum many-body systems and focus on cases in which they occur through a transition that is controlled by a model parameter, a…
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A Unified Framework for Locally Stable Phases
arXiv quant-ph
arXiv:2605.00088v2 Announce Type: replace Abstract: We propose a unifying framework for characterizing pure and mixed state phases of matter across equilibrium, non equilibrium, and metastable regimes. We introduce the concept of locally…
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Complementary Quantum Time Distributions from a Single Operational Protocol
arXiv quant-ph
arXiv:2604.10339v3 Announce Type: replace Abstract: A single operational protocol based on free evolution and projective measurements yields inequivalent quantum time distributions through distinct post-processing procedures. We construct…
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Preprocessing noise in finite-size quantum key distribution
arXiv quant-ph
arXiv:2603.18213v2 Announce Type: replace Abstract: It is known that trusted, preprocessing noise may boost quantum key distribution by expanding the range of values of tolerated noise. For BB84, adding trusted noise may allow the…
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Millimeter Wave Readout of a Superconducting Qubit
arXiv quant-ph
arXiv:2603.13837v2 Announce Type: replace Abstract: Millimeter waves are emerging as an enabling technology for connecting and enhancing different quantum platforms such as Rydberg atoms, optomechanics, and superconducting qubits. In this…
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Bandwidth-Cost Reduction for Photon-Matter Simulation at the Single-Photon Level
arXiv quant-ph
arXiv:2601.15945v3 Announce Type: replace Abstract: Simulations of quantum dynamics of traveling photons interacting with matter can be used to model and design photonic quantum-network components. Such simulations require selecting a…
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A $k$-entanglement measure complying with the many-body resource theory and its evaluation
arXiv quant-ph
arXiv:2512.12588v2 Announce Type: replace Abstract: $k$-entanglement provides a hierarchical characterization of multipartite correlations according to their entanglement structure, ranging from multipartite entanglement ($k=n$) to genuine…
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Separation-Dependent Bell Correlations from Prepared Coherence in Dirac Wavepackets
arXiv quant-ph
arXiv:2511.12258v3 Announce Type: replace Abstract: We calculate separation-dependent Bell correlations for a fixed pair of Dirac electron wavepackets in a free, weakly relativistic packet model, treating the prepared joint wave as a…
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Levitated optomechanics with cylindrically polarized vortex beams
arXiv quant-ph
arXiv:2510.05384v2 Announce Type: replace Abstract: Optically levitated and cooled nanoparticles are a new quantum system whose application to the creation of non-classical states of motion and quantum limited sensing is fundamentally…
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Explicit construction of a 2-design of ${\rm U}(2)$ from the theory of angular momentum
arXiv quant-ph
arXiv:2509.17127v2 Announce Type: replace Abstract: The main aim of this work is to present an explicit construction of a 2-design of ${\rm U}(2)$, relying only on a tool that belongs to every physicists toolbox: the theory of angular…
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Unitary Closed Timelike Curves can Solve all of NP
arXiv quant-ph
arXiv:2410.04630v2 Announce Type: replace Abstract: Born in the intersection between quantum mechanics and general relativity, indefinite causal structure is the idea that in the continuum of time, some sets of events do not have an…
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Functional Tensor Trains for High-Order Greeks and Exposure Tails of Multi-Asset Structured Products
arXiv quant-ph
arXiv:2610.42119v1 Announce Type: cross Abstract: Risk management of worst-of autocallables needs price sensitivities (Greeks) up to third order and the potential future exposure, a tail quantile of the note's future value. In Monte Carlo…
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Charge Pumping Leptogenesis from the Symmetric Mass Generation Phase on a Four-Leg Ladder Lattice
arXiv quant-ph
arXiv:2610.42103v1 Announce Type: cross Abstract: Quantized charge pumping in quantum Hall systems is a bulk topological property, typically manifesting on gapless boundaries as spectral flow through chiral edge modes upon flux insertion…
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Solvable coupled cluster states in $d=\infty$ with prescribed momentum distribution
arXiv quant-ph
arXiv:2610.41976v1 Announce Type: cross Abstract: Two of the most successful ideas in many-body theory, the exponential coupled cluster ansatz and DMFT, have to date developed separately. We establish a connection between them, by showing…
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The Role of Electron-Nuclear Coupling on Chemical and Physical Processes
arXiv quant-ph
arXiv:2610.41898v1 Announce Type: cross Abstract: Over the last few decades, Born-Oppenheimer (BO) and Born-Oppenheimer-Huang (BOH) treatments for electron-nuclear equation of motion have been considered as the cornerstone for qualitative…
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Channel dichotomies
arXiv quant-ph
arXiv:2610.41858v1 Announce Type: cross Abstract: We study channel interconversion under non-signalling superchannels, where the asymptotic conversion rate is given by the ratio of the channel capacities. Our main result determines the…
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Mathematical foundations of second quantization: an introduction through spin-boson models
arXiv quant-ph
arXiv:2610.41657v1 Announce Type: cross Abstract: These lecture notes originate from a one-semester course on the mathematical foundations of second quantization, first given at the Department of Physics of the…
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Longitudinal electric corner modes in continuum quantum gauge theory with matter
arXiv quant-ph
arXiv:2610.41240v1 Announce Type: cross Abstract: Subregions in gauge theories give rise to edge modes and corner charges supported on their boundaries. While this is well-established classically and in quantum lattice gauge theories, the…
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Induced Lorentzian geometry from the fermionic quantum metric
arXiv quant-ph
arXiv:2610.41138v1 Announce Type: cross Abstract: Quantum geometry is conventionally understood in parameter or momentum space and need not be related to a geometry in configuration space. Here we show for Dirac fermions in a background…
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Exact Electron Dynamics in Linear and Chiral Cavities: Complete Field versus Single-Helicity Reduction
arXiv quant-ph
arXiv:2610.40986v1 Announce Type: cross Abstract: Can a chiral cavity turn a free electron into a Landau-like orbiting particle? We answer with exact solutions of three quadratic electron--cavity models in the dipole limit, valid at…
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Microscopic Theory of Spin-Orbit Interactions of Light
arXiv quant-ph
arXiv:2610.40979v1 Announce Type: cross Abstract: Optical spin-orbit interactions (SOI), demonstrated experimentally in optical cavities, enable the polarization degrees of freedom of light to be described and controlled as an effective…
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Proof of the entropic $c$-theorem
arXiv quant-ph
arXiv:2610.40874v1 Announce Type: cross Abstract: We prove an entropic $c$-theorem in two dimensions by constructing a $c$-function from the mutual information between spacelike separated wedges, defined through the relative entropy. The…
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Singlet-Triplet Transition of Rotating Moir\'e Atoms in a Magnetic Field
arXiv quant-ph
arXiv:2610.40786v1 Announce Type: cross Abstract: Moir\'e superlattices can bind several electrons to each potential minimum, forming few-electron "moir\'e atoms." Using neural quantum states that obey magnetic periodic boundary…
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Secret-shared teleportation of a two-qudit gate with a deferred recipient
arXiv quant-ph
arXiv:2610.42150v1 Announce Type: new Abstract: An unknown quantum operation, like an unknown quantum state, cannot be perfectly copied or stored for later use. A specific gate can be embedded in an entangled resource and teleported, but…
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Weighted hypergraph states as a resource for quantum metrology
arXiv quant-ph
arXiv:2610.42129v1 Announce Type: new Abstract: Quantum correlations can be used to improve sensing precision beyond classical limits, yet the correlated resource states needed can be challenging to prepare and preserve. Here, we study the…
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The Quartic Gap Between Quantum and Dequantized Algorithms for Linear Algebra Is Tight
arXiv quant-ph
arXiv:2610.42069v1 Announce Type: new Abstract: Quantum algorithms for linear algebra that access a matrix $A$ through quantum random access memory (QRAM) prepare quantum states proportional to the solutions of linear systems and related…
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Benchmarking Single-Photon Sources for Measurement-Device-Independent Quantum Key Distribution
arXiv quant-ph
arXiv:2610.42041v1 Announce Type: new Abstract: Measurement-Device-Independent Quantum Key Distribution (MDI-QKD) enables secure communication without trusting the measurement devices, but its performance critically depends on the quality…
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No generalised contextuality from the vacuum
arXiv quant-ph
arXiv:2610.41964v1 Announce Type: new Abstract: We show that, under certain conditions, generalised contextuality, in the sense introduced by Spekkens, cannot be created from the vacuum of a quantum field. Initial noncontextual qudit…
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Locality, Probability and the Relevance of History
arXiv quant-ph
arXiv:2610.41944v1 Announce Type: new Abstract: Relativistic theory and experiments teach us that causal influences are constrained by the speed of light. Deterministic theories incorporate this lesson in $\textit{functional}$ terms…
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Lifting the mixed to the pure: quantum phases of matter from canonical purification
arXiv quant-ph
arXiv:2610.41926v1 Announce Type: new Abstract: Pure-state quantum phases are defined through finite-depth local unitary connections. This concept of phases has recently been generalized to mixed states in terms of locally reversible…
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Control-Noise Trade-offs in Industrially Integrated ${}^{28}\mathrm{Si}/\mathrm{SiGe}$ Spin-1/2 Qubits
arXiv quant-ph
arXiv:2610.41890v1 Announce Type: new Abstract: Scaling silicon spin qubits to fault-tolerant processors requires semiconductor foundry integration, yet it remains unclear how industrial fabrication and dense device integration affect…
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Engineered Learning Problems on Noisy Quantum Processors
arXiv quant-ph
arXiv:2610.41848v1 Announce Type: new Abstract: Despite quantum machine learning being an active topic of research, demonstrations of algorithms run on quantum hardware beating classical methods remain rare. In this work, we demonstrate a…
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Bounding Fidelity of Non-Stabilizer States from Local Pauli Measurements
arXiv quant-ph
arXiv:2610.41808v1 Announce Type: new Abstract: Nonstabilizerness, commonly referred to as magic, is essential for universal quantum computation. Yet, for pure $n$-qubit states this property is directly linked to the hardness of direct…
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Chiral Torsional Double Wells: Tunneling and Polarizability
arXiv quant-ph
arXiv:2610.41782v1 Announce Type: new Abstract: Quantum tunneling between mirror-related wells of a torsional potential sets the timescale for coherent interconversion of chiral conformers. We ask whether slower tunneling also weakens the…
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Device-independent conference key agreement from two-body correlators with balanced Dicke states
arXiv quant-ph
arXiv:2610.41712v1 Announce Type: new Abstract: Device-independent conference key agreement (DI-CKA) enables $N > 2$ distant parties to establish a common secret key without detailed characterization of the source or measurement devices…
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Exponential quantum-classical query separations for cyclic Forrelation
arXiv quant-ph
arXiv:2610.41694v1 Announce Type: new Abstract: We study the randomized classical query complexity of cyclic Forrelation, a cyclic analogue of $k$-Forrelation [AA15, STOC'15; BS21, STOC'21]. Given $k$ Boolean functions…
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Solving the MAX-$k$-CUT problem for hypergraphs with quantum computing
arXiv quant-ph
arXiv:2610.41678v1 Announce Type: new Abstract: We investigate the MAX-$k$-CUT problem on hypergraphs by considering their representation as spin systems with Ising interactions. The corresponding cost Hamiltonian for MAX-$k$-CUT problem…
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Windowed Catodyne Measurements: Continuum Approximation versus Exact Discrete Photon-Number Treatment
arXiv quant-ph
arXiv:2610.41626v1 Announce Type: new Abstract: We analyze a family of measurements obtained by retaining only a finite window of the photon-sum variable in catodyne detection, where a Schr\"odinger cat state serves as the local…
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FaultScope: A software package for fast error attribution in quantum error correction
arXiv quant-ph
arXiv:2610.41528v1 Announce Type: new Abstract: We introduce FaultScope, a classical simulator for quantum error correction circuits, implemented in Rust with a Python interface. FaultScope estimates logical error rates and their…
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High-efficiency photonic GHZ measurements with linear optics
arXiv quant-ph
arXiv:2610.41524v1 Announce Type: new Abstract: Probabilistic and destructive Bell-measurements, also known as fusions, constitute a fundamental primitive for photonic quantum technologies. These operations rely only on pairwise photonic…
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An Unbounded Separation of Almost-Quantum and Commuting-Operator Correlations in Zero-Error Communication
arXiv quant-ph
arXiv:2610.41448v1 Announce Type: new Abstract: Almost-quantum correlations form the $\mathtt{1+AB}$ level of the Navascu\'es--Pironio--Ac\'in hierarchy. They strictly contain the quantum set, are characterized by a single semidefinite…
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Almost-Quantum Correlations Violate Information Causality
arXiv quant-ph
arXiv:2610.41444v1 Announce Type: new Abstract: Information causality (IC) posits that communicating m classical bits cannot give the receiver access to more than m bits of information about the sender's independent data. Although IC holds…
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oracq: A Modular Framework for Implementing and Analyzing Quantum Scientific Computing Algorithms
arXiv quant-ph
arXiv:2610.41431v1 Announce Type: new Abstract: Quantum algorithms for scientific computing are specified against access models such as block-encodings, sparse oracles, state preparations, and quantum random-access memories. Their concrete…
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Analytic level statistics of the quantum Rabi model
arXiv quant-ph
arXiv:2610.41421v1 Announce Type: new Abstract: We derive an analytic expression for the distribution of level spacings in the quantum Rabi model. At high energies, the spectrum in a fixed parity sector takes the asymptotic form of a…
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Helper-assisted quantum sensing with low dressed-state leakage
arXiv quant-ph
arXiv:2610.41404v1 Announce Type: new Abstract: We study a two-qubit sensing protocol in which only a helper qubit is read out. Calibrated loading and unloading encode a transverse signal in the helper's phase, keep leakage out of a…
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Time-Domain Multiplexing for Resource-Efficient Heralded GKP State Preparation
arXiv quant-ph
arXiv:2610.41341v1 Announce Type: new Abstract: Gottesman-Kitaev-Preskill (GKP) states are key resources for fault-tolerant photonic quantum computing, but their conditional preparation via Gaussian boson sampling involves a trade-off…
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Parametric Enhancement of an Optical Spring in a Dark Signal-Recycling Cavity
arXiv quant-ph
arXiv:2610.41270v1 Announce Type: new Abstract: Optical springs tailor the response of precision sensors. Parametric amplification of the signal field stiffens the spring, extending the precision to higher frequencies. A Michelson…
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Biorthogonal universal quantum control
arXiv quant-ph
arXiv:2610.41195v1 Announce Type: new Abstract: As a paradigm for describing open-quantum-system dynamics, the non-Hermitian Schr\"odinger equation generally modifies state norms, complicating coherent control over the system's Hilbert…
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Anomalous superradiant phases in a quantum Rabi zigzag chain under a synthetic gauge field
arXiv quant-ph
arXiv:2610.41194v1 Announce Type: new Abstract: We present the phase diagram of a one-dimensional quantum Rabi zigzag chain under an artificial gauge field, which is implemented via phase-modulated next-nearest-neighbor (NNN) hopping. For…
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Quantum query complexity of Hurwitz stability testing
arXiv quant-ph
arXiv:2610.41180v1 Announce Type: new Abstract: Determining whether every trajectory of the linear system $\dot{x}=Ax$ converges to zero (or, equivalently, whether $A$ is Hurwitz stable) is a fundamental problem in control theory. It…
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Quantum Vehicle Routing Problem: a smart initialization strategy for ill-conditioned optimization landscapes
arXiv quant-ph
arXiv:2610.41120v1 Announce Type: new Abstract: With the expansion of complex transport infrastructure, new paths for linking different destinations have emerged, allowing the definition of multiple routes. The introduction of new roads…
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Vacuum amplification across a programmable bosonic Bogoliubov stability boundary in a trapped-ion chain
arXiv quant-ph
arXiv:2610.41033v1 Announce Type: new Abstract: A quantum oscillator always carries vacuum fluctuations, and modulating its parameters converts them into correlated pairs of real quanta. This vacuum amplification underlies squeezed light…
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Variational Programs with Open Clocks
arXiv quant-ph
arXiv:2610.40988v1 Announce Type: new Abstract: Variational quantum algorithms leave the durations of Hamiltonian evolutions open for a classical optimizer to set. We present VHamilton, a minimal extension of the Hamilton quantum…
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Optical Quantum Memory Processing for Quantum Hashing
arXiv quant-ph
arXiv:2610.40904v1 Announce Type: new Abstract: Sender authentication is an important requirement for secure quantum communication networks. We propose programmable photon-echo quantum memory processing of a multi-time-bin photonic qudit…
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Quantum Batteries in two-dimensional material-based Josephson Junctions
arXiv quant-ph
arXiv:2605.22582v2 Announce Type: replace-cross Abstract: We investigate the solid-state implementation of a Dicke-like quantum battery consisting of a two-dimensional material-based Josephson junction inductively coupled to a resonator…
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Electronic-Structure-Informed Many-Body Encoding for Quantum Machine Learning
arXiv quant-ph
arXiv:2610.40840v1 Announce Type: new Abstract: Data encoding is a central challenge in quantum machine learning (QML), as it determines how classical information is mapped onto quantum states and influences the expressive power and…
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Fock-space delocalization and its control in scarred-vs-ergodic dynamics
arXiv quant-ph
arXiv:2610.40805v1 Announce Type: new Abstract: Quantum many-body scarred dynamics in Rydberg-atom arrays is characterized by revivals, in which the system repeatedly returns to its initial state despite its many-body complexity. But how…
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A Universal Approach to Hydrodynamics in Higher Dimensions via Tensor Networks
arXiv quant-ph
arXiv:2610.40776v1 Announce Type: new Abstract: Extracting late-time hydrodynamic transport properties directly from microscopic quantum models, especially in dimensions beyond one, is believed to be classically intractable. This owes, in…
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Finite-Element Electromagnetic Analysis and Evaluation of Antenna Performance Metrics Using a Quantum Linear System Solver
arXiv quant-ph
arXiv:2610.40693v1 Announce Type: new Abstract: Electromagnetic analysis based on the finite element method is widely used in antenna design. At higher frequencies, however, the required mesh refinement makes solving large sparse linear…
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Clifford synthesis is NP-complete
arXiv quant-ph
arXiv:2610.40886v1 Announce Type: new Abstract: We show that the problem of synthesizing a quantum circuit for a given Clifford operator using at most a specified amount of resources is NP-complete for several resource models of practical…
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Grow, Compress, and Perturb: A Hybrid Quantum-Classical Pathway to Scalable Quantum Chemistry on Quantum Computers
arXiv quant-ph
arXiv:2610.40561v2 Announce Type: replace Abstract: While Variational Quantum Eigensolver (VQE) variants are among the leading candidates for electronic structure calculations on quantum computers, gradient-based operator selection limits…
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Resonance and Transition-Channel Competition in Cavity-Assisted Floquet-State Stabilization
arXiv quant-ph
arXiv:2610.39169v2 Announce Type: replace Abstract: Static coupling to a dissipative cavity has been proposed as a route to autonomously stabilize Floquet eigenstates. The cavity provides an energy-selective relaxation channel: when its…
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Information and reference requirements for auditing collider classifiers
arXiv quant-ph
arXiv:2609.02781v2 Announce Type: replace Abstract: Assertions about collider classifiers require observable evidence and a specified deployment reference. We distinguish the classification threshold that selects events from the claim…
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Sample complexity of quantum resource testing via one-shot quantum blurring
arXiv quant-ph
arXiv:2607.24712v3 Announce Type: replace Abstract: Quantum resource testing is a fundamental primitive of quantum information processing, profoundly connected to resource manipulation. Its goal is to discriminate $n$ copies of a given…
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Toward Quantum Utility in Correlated Topological Matter: Variational Preparation of Fractional Quantum Hall Manifolds
arXiv quant-ph
arXiv:2607.11380v2 Announce Type: replace Abstract: We investigate the use of variational quantum algorithms to prepare and characterize fractional quantum Hall states on near-term quantum processors. Focusing on the $\nu=1/3$ Laughlin…
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Time Crystals on Quantum Devices
arXiv quant-ph
arXiv:2605.27211v2 Announce Type: replace Abstract: Time crystals are nonequilibrium phases of matter characterized by the emergence of temporal ordering, in which an interacting many-body system develops robust structure in its time…
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Syndrome resampling enhances quantum error correction thresholds
arXiv quant-ph
arXiv:2605.06101v2 Announce Type: replace Abstract: Quantum error correction (QEC) enables fault-tolerant quantum computation but requires operating quantum hardware at physical error rates below code-dependent thresholds, which remains…
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Entanglement cost in non-local quantum computation
arXiv quant-ph
arXiv:2605.02840v4 Announce Type: replace Abstract: This is a book-length treatment of the subject of non-local quantum computation (NLQC). NLQC is a method for implementing quantum operations that interact two systems without directly…
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Quantum Riemannian Hamiltonian Descent
arXiv quant-ph
arXiv:2603.28624v2 Announce Type: replace Abstract: We propose Quantum Riemannian Hamiltonian Descent (QRHD), a quantum algorithm for continuous optimization on Riemannian manifolds that extends Quantum Hamiltonian Descent (QHD) by…
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Rotating-Wave and Secular Approximations for Open Quantum Systems
arXiv quant-ph
arXiv:2603.26606v3 Announce Type: replace Abstract: We derive a nonperturbative bound on the distance between evolutions of open quantum systems described by time-dependent generators. We show how this result can be employed to provide an…
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Combinatorial Matrix Functions in Ising Models and Quantum Circuit Representation
arXiv quant-ph
arXiv:2602.01868v3 Announce Type: replace Abstract: Permanents, hafnians, and loop-hafnians are combinatorial matrix functions defined on the perfect matchings of graphs. These matrix functions arise in the quantum amplitudes for output…
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Quantum Noise Spectroscopy of Nanoscale Charge Defects in Silicon Carbide at Room Temperature
arXiv quant-ph
arXiv:2512.22521v2 Announce Type: replace Abstract: The nanoscale charge environment critically influences the performance of semiconductor devices, yet traditional characterization techniques usually lack the spatial resolution to resolve…
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Witnessing Short- and Long-Range Nonstabilizerness via the Information Lattice
arXiv quant-ph
arXiv:2510.26696v2 Announce Type: replace Abstract: We study nonstabilizerness on the information lattice and demonstrate that noninteger local information directly indicates nonstabilizerness. For states with a clear separation of short…