Quantum Computing
Quantum Computing news — Wednesday 30 September 2026
150 stories from 3 sources, every one in English. Each links to its publisher.
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Charles Black Leads C2QA Research on Scalable Quantum Computing
The Quantum Insider
Insider Brief Charles Black, director of Brookhaven National Laboratory ’s Co-design Center for Quantum Advantage (C2QA), is applying decades of materials science and semiconductor research to quantum computing. C2QA researchers are…
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New Report Positions Florida as an Emerging Leader in Defense-Led Quantum Technology
The Quantum Insider
Insider Brief A Quantum Insider report commissioned by FloridaCommerce identifies defense and practical deployment as central to Florida’s quantum technology opportunities. The assessment identifies post-quantum cryptography, quantum…
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Classiq Introduces Fault Tolerance Engine for Quantum Applications
The Quantum Insider
Insider Brief Classiq introduced its Fault Tolerance Engine to translate optimized logical quantum programs into architecture-aware fault-tolerant execution plans. The engine estimates physical qubit requirements, error-correction cycles…
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Quantum eMotion to Acquire Plurilock Security
The Quantum Insider
Insider Brief Quantum eMotion has entered a definitive agreement to acquire Plurilock Security in a proposed transaction that would expand QeM’s quantum-secure cybersecurity business with an established commercial platform. The proposed…
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QuantLase Tests Photonic Computing Platform on Financial Market Data
The Quantum Insider
Insider Brief QuantLase says it tested its PIPU photonic computing platform on seven financial market datasets to evaluate how optical dynamics can process changing information and generate predictions. The experiments combined physical…
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NSF Awards $600,000 to Stony Brook and University of Hawaiʻi to Advance Distributed Quantum Intelligent Sensor Networks
Quantum Computing Report
Researchers at Stony Brook University and the University of Hawaiʻi at Mānoa have been awarded a $600,000 NSF grant to develop Quantum Intelligent Sensor Networks (QISNs). This project aims to advance quantum metrology by engineering…
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UC Santa Barbara Researchers Join Three NSF Quantum Leap Challenge Institutes Under $290 Million Portfolio Renewal
Quantum Computing Report
UCSB faculty will participate in three NSF Quantum Leap Challenge Institutes (QLCI), sharing $290 million in renewed and new funding. This initiative, under the National Quantum Initiative Act, focuses on accelerating quantum research into…
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NATO Sets Quantum Roadmap For Military Trials And Secure Communications
The Quantum Insider
Insider Brief NATO’s new quantum roadmap sets priorities and deadlines for testing military applications, protecting communications and preparing allied forces to adopt quantum technologies. Planned activities include quantum sensing sea…
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Diraq Expands U.S. Footprint with New Mexico Quantum R＆D Laboratory to Advance DARPA QBI Milestones
Quantum Computing Report
Diraq is expanding its U.S. operations by opening a new quantum R&D lab in Albuquerque, New Mexico, in collaboration with the New Mexico Technology and Innovation Office and Roadrunner Venture Studios. This expansion, supported by New…
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Roadrunner Quantum Lab Opens 35,000-Square-Foot Albuquerque Facility with Initial Cohort of Quantum Startups, National Labs, and Ecosystem Partners
Quantum Computing Report
The Roadrunner Quantum Lab (RQL) has opened a 35,000-square-foot facility in Albuquerque, New Mexico, serving as a hub for quantum technology testing and commercialization. Supported by $25 million in state funding, it houses 15 quantum…
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New Quantum Algorithm Targets Bottleneck in Fluid-Flow Modeling
The Quantum Insider
Insider Brief Oak Ridge National Laboratory researchers developed LuGo, a quantum algorithm that reduced quantum gate requirements by more than 95% in a fluid-flow modeling problem. LuGo performs more calculations on classical computers…
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French National Quantum Update: September 2026
The Quantum Insider
Executive Summary The summer break is definitely over. France’s quantum sector focused on the manufacturing, software and commercial relationships needed to put quantum computers into wider use in September 2026. Quobly reported progress…
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Cloudflare Launches Public Certificate Authority to Secure the Web Against Quantum Threats
Quantum Computing Report
Cloudflare is becoming a public Certificate Authority (CA) to secure the web against quantum threats by introducing an open, automated, and high-scale issuance service. This initiative will provide both classical TLS certificates and…
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Xanadu and Bluefors Form Multi-Million Dollar Strategic Partnership to Develop Modular Cryogenic Infrastructure for Utility-Scale Quantum Data Centers
Quantum Computing Report
Xanadu and Bluefors have formed a multi-million dollar partnership to develop a modular cryogenic infrastructure for utility-scale quantum data centers. Their joint effort focuses on replacing large, centralized cryoplants with compact…
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Project Eleven Acquires Riva Labs to Scale Post-Quantum Cryptography and Blockchain Infrastructure Stack
Quantum Computing Report
Project Eleven has acquired Riva Labs to create a comprehensive post-quantum cryptography and blockchain infrastructure. This merger addresses vulnerabilities in current public-key cryptography by integrating quantum-resistant solutions…
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Infleqtion and Riverlane Execute Strategic MOU to Integrate Neutral-Atom Hardware with Real-Time QEC Decoders
Quantum Computing Report
Infleqtion and Riverlane have partnered to integrate real-time quantum error correction with neutral-atom hardware. This collaboration aims to close the latency gap in qubit error detection and processing, enabling scalable logical qubits…
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Royal Bank of Canada Launches Enterprise Quantum Strategy and Academic Workforce Pipelines
Quantum Computing Report
Royal Bank of Canada (RBC) has launched a multi-year enterprise quantum strategy focusing on internal R&D, post-quantum cybersecurity, academic partnerships, and hardware investments. This initiative includes collaborations with Xanadu…
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IRIS: A Compiler for Distributed Quantum Systems
arXiv quant-ph
arXiv:2605.21795v2 Announce Type: replace Abstract: Distributed Quantum Computers (DQCs) enable large system sizes by connecting smaller chips via photonic interconnects. DQCs use teleportation to relocate qubits and execute CNOTs between…
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Fewer Qubits, Better Choices: Coupling-Aware Sub-QUBO Selection for Quantum-Assisted Traffic Zone Partitioning
arXiv quant-ph
arXiv:2609.32627v1 Announce Type: new Abstract: Near-term quantum optimizers accommodate roughly a hundred binary variables, requiring large Quadratic Unconstrained Binary Optimization problems to be decomposed into hardware-sized…
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Exact Gaussian Entanglement Dynamics and Initial-State Control in Coupled Parametric Oscillators
arXiv quant-ph
arXiv:2609.32709v1 Announce Type: new Abstract: We study two bilinearly coupled harmonic oscillators driven by a common time-dependent spring. A fixed normal-mode transformation reduces the pair to two parametric oscillators, each solved…
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Quantum Machine Learning for Cybersecurity Applications: Simulation and Hardware Validation
arXiv quant-ph
arXiv:2609.32911v1 Announce Type: new Abstract: Under tight feature and compute budgets, classical threat detection pipelines often degrade on near-decision-boundary events. Small quantum processors are now available, but existing work…
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The wiring sets a phase-blind quantum memory's gap, the weight caps its coherence
arXiv quant-ph
arXiv:2609.32943v1 Announce Type: new Abstract: Engineered dissipation corrects errors, yet a memory's phase decays. What the memory's gap measures is not settled. Here we show that when each jump resets one basis state, the wiring can set…
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Preparation-controlled relaxation in an overdamped RLC circuit: A pedagogical route to the spectral Mpemba effect
arXiv quant-ph
arXiv:2609.33277v1 Announce Type: new Abstract: Can a system with more stored energy cool faster than one with less? An overdamped resistor--inductor--capacitor (RLC) circuit offers a classical, experimentally accessible spectral Mpemba…
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Terminal-Register Certification for Finite-Measurement Learning of Multiscale Quantum States
arXiv quant-ph
arXiv:2609.33567v1 Announce Type: new Abstract: Structured quantum-state learning not only depends on an expressive ansatz but also on an operational certificate that stays meaningful with finite measurements and imperfect implementation…
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Nakayama's reduction of quantum topos and Bayesian quantum computing
arXiv quant-ph
arXiv:2609.34200v1 Announce Type: new Abstract: Nakayama found the way to limit the contexts in the D\"oring-Isham topos quantum theory and unified such limitation and the definition of probability as a single choice of topology. We…
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Cubic Phase Gate with a Trapped Ion Oscillator
arXiv quant-ph
arXiv:2609.34774v1 Announce Type: new Abstract: The motional modes of trapped ions are promising candidates for continuous-variable (CV) quantum computation and simulation. However, to achieve a universal gate set for CV quantum…
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From Quantum to Classical Dissipative Spin Dynamics
arXiv quant-ph
arXiv:2609.35112v1 Announce Type: new Abstract: The Landau-Lifshitz-Gilbert (LLG) equation provides the fundamental description of dissipative magnetization dynamics. A recently proposed quantum analog, the quantum Landau-Lifshitz-Gilbert…
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Accurate and bounded approximation of quantum correlation functions
arXiv quant-ph
arXiv:2609.35114v1 Announce Type: new Abstract: The exact classical simulation of non-integrable quantum systems rapidly becomes intractable beyond small system sizes, yet its role is central to predicting many-body dynamics. Approximate…
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Asymptotically Good Quantum Codes with Addressable Transversal T Gates
arXiv quant-ph
arXiv:2609.35129v1 Announce Type: new Abstract: Designing quantum codes with both transversal non-Clifford gates and good error-correcting parameters is an important goal in fault-tolerant quantum computation. Here, we construct an…
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Weakly interacting fermionic Gibbs states are Gaussian mixtures and classically simulable
arXiv quant-ph
arXiv:2609.35159v1 Announce Type: new Abstract: Identifying regimes in which interacting fermionic systems admit efficient classical simulation is a crucial task in quantum many-body physics. In this work, we rigorously establish the…
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Sublinear Copies Suffice for Fidelity Estimation with Pauli Measurements
arXiv quant-ph
arXiv:2609.35547v1 Announce Type: new Abstract: We present a protocol that estimates the quantum fidelity, up to precision $\varepsilon$, between a known target state and unknown lab-prepared state with sublinear…
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Exponential lower bounds for low-degree strategies in position-based quantum cryptography
arXiv quant-ph
arXiv:2609.35592v1 Announce Type: new Abstract: Non-local quantum computation (NLQC) consists on the implementation of a bipartite unitary $U_{AB}$ by two cooperating distant players by means of a two-round protocol with a single…
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Locality of KMS states for infinite fermionic lattice systems
arXiv quant-ph
arXiv:2609.31858v1 Announce Type: cross Abstract: We study how thermal equilibrium states of infinite fermionic lattices respond to perturbations of the Hamiltonian. Our main result concerns extensive perturbations of a chosen KMS state…
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Facial classification Using Hybrid Quantum Machine Learning
arXiv quant-ph
arXiv:2609.31915v1 Announce Type: cross Abstract: Hybrid quantum methods have received limited study for resource-constrained facial biometrics. We present a hybrid quantum-classical facial recognition pipeline designed to run on standard…
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Quantum undular bores, rainbows, and event horizons in superfluid dam breaks
arXiv quant-ph
arXiv:2609.32232v1 Announce Type: cross Abstract: The sudden removal of a potential barrier from a Bose-Einstein condensate (BEC) gives rise to a quantum version of a hydrodynamic dam break and leads to rich wave dynamics that have…
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Wide-Mass-Scanning-Range Setup and Phase-Resolved Protocol for Axion Dark Matter Detection
arXiv quant-ph
arXiv:2609.32554v1 Announce Type: cross Abstract: We propose a paradigm for quantum enhanced axion dark matter search, which does not rely on power measurements. We propose to measure directly the axion amplitude and phase in an…
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Native implementation of the machine-learned Skala exchange-correlation functional in CP2K: Unified one-centre reconstruction for molecular and condensed-phase calculations
arXiv quant-ph
arXiv:2609.34055v1 Announce Type: cross Abstract: We implement the machine-learned Skala exchange-correlation (XC) functional natively in CP2K using its Gaussian and plane-wave (GPW) and Gaussian and augmented-plane-wave (GAPW) methods. A…
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Nuclear scattering phase shifts with factorized geometric-time RODEO on a quantum processor
arXiv quant-ph
arXiv:2609.34298v1 Announce Type: cross Abstract: We reconstruct elastic $s$-wave neutron-proton ($np$) phase shifts from trapped spectra measured on IBM Aachen using a compressed RODEO circuit. For a schematic square-well interaction…
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Discontinuity of Continuum Fermion Dynamics
arXiv quant-ph
arXiv:2609.34402v1 Announce Type: cross Abstract: We study the Heisenberg dynamics of continuum fermions in $\IR^d$ interacting through a pair potential. For a large class of nonconstant pair potentials and under suitable assumptions on…
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Quantum observers can communicate across multiverse branches
arXiv quant-ph
arXiv:2601.08102v3 Announce Type: replace Abstract: It is commonly thought that observers in distinct branches of an Everettian multiverse cannot communicate without violating the linearity of quantum theory. Here we show a counterexample…
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Exact quantum transport in non-Markovian open Gaussian systems
arXiv quant-ph
arXiv:2602.21190v2 Announce Type: replace Abstract: We build an exact framework to evaluate heat, energy, and particle transport between Gaussian reservoirs mediated by a quadratic quantum system. By combining full counting statistics with…
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Synchronization in a dissipative quantum many-body system
arXiv quant-ph
arXiv:2604.18707v2 Announce Type: replace Abstract: We study synchronization in the XX qubit chain subject to local or multi-local amplitude-damping noise. Analyzing the decoherence-free subspace (DFS) structure of the model, we show that…
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Learning error suppression strategies for dynamic quantum circuits
arXiv quant-ph
arXiv:2604.18734v3 Announce Type: replace Abstract: Dynamic quantum circuits integrate unitary evolution with mid-circuit measurement and feedforward, enabling conditional operations essential for efficient quantum algorithms and…
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Characterising the precision of a clock without any external time reference
arXiv quant-ph
arXiv:2609.31832v1 Announce Type: new Abstract: Determining a clock's precision usually requires comparison with a better time reference, yet no ideal reference is physically attainable. We show how a single clock can characterise its own…
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Microwave Power-to-Frequency Transduction in a Magnetically Initiated Rydberg Dissipative Time Crystal
arXiv quant-ph
arXiv:2609.31824v1 Announce Type: cross Abstract: Microwave power-to-frequency transduction is demonstrated using the emergent oscillation frequency of a magnetically initiated Rydberg dissipative time crystal (DTC). In a room-temperature…
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Solving larger Travelling Salesman Problem networks with a penalty-free Variational Quantum Algorithm
arXiv quant-ph
arXiv:2512.06523v2 Announce Type: replace Abstract: The Travelling Salesman Problem (TSP) is a well-known NP-hard combinatorial optimisation problem with important industrial applications. Although extensively studied, quantum solutions…
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Optimal physical approximations of pure-state cloning and transposition are complementary channels
arXiv quant-ph
arXiv:2603.23628v3 Announce Type: replace Abstract: State cloning and state transposition are fundamental transformations that, despite being desirable, cannot be perfectly realised as a consequence of two distinct requirements of quantum…
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Macroscopic entanglement between two magnon modes via two-tone driving of a superconducting qubit
arXiv quant-ph
arXiv:2605.06297v2 Announce Type: replace Abstract: The cavity-mediated coupling between magnons in an yttrium-iron-garnet (YIG) sphere and a superconducting qubit has recently been demonstrated as a new platform for preparing macroscopic…
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Quantum Error Correction and the Limits of Quantum Metrology
arXiv quant-ph
arXiv:2605.24120v2 Announce Type: replace Abstract: Quantum metrology has been making amazing progress in the past decades. It is always in researchers' interest to search for new optimal states that improve parameter estimation. In this…
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Equivalence of non-local computation tasks beyond Clifford operations
arXiv quant-ph
arXiv:2606.26354v2 Announce Type: replace Abstract: Non-local quantum computation (NLQC) studies how two collaborating players can implement channels on distributed systems using a single simultaneous round of quantum communication and…
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Deleterious effect of photon-phonon coupling on microcavities in their application as quantum sources
arXiv quant-ph
arXiv:2607.21743v2 Announce Type: replace Abstract: In quantum systems, the contact with the environment is detrimental to the purity of the state, thus limiting the practical use of entangled sources in quantum information applications…
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Hardware-Efficient Exchange-Only QML: Singlet-Triplet Spin Chains via Inter-pair Coupling without Magnetic Gradients
arXiv quant-ph
arXiv:2608.29017v3 Announce Type: replace Abstract: Standard universal quantum computing using exchange-only qubits typically requires three physical spins per logical qubit, leading to significant hardware overhead. Conversely, two-spin…
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The ZZ feature map induces a signless Laplacian metric: a closed-form classical surrogate for quantum kernel regression
arXiv quant-ph
arXiv:2608.29422v2 Announce Type: replace Abstract: Bandwidth-tuned quantum kernels have been shown to lose their advantage over classical kernels and to resemble radial basis function kernels, but the analytical support for that…
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Vanilla Exact Synthesis of CNOT Circuits is NP-hard
arXiv quant-ph
arXiv:2609.04160v2 Announce Type: replace Abstract: Exact CNOT synthesis seeks a minimum-size circuit implementing a given invertible binary linear transformation. We study its vanilla formulation: synthesis from the identity on fixed…
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Certifying bipartite entanglement on a superconducting processor from a corrected QAOA cost layer
arXiv quant-ph
arXiv:2609.09495v2 Announce Type: replace Abstract: The Quantum Approximate Optimisation Algorithm is the canonical near-term heuristic, yet on real superconducting hardware its behaviour is set by device physics, not by the algorithm…
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3D $\mathcal{N}=1$ supergravity from Virasoro TQFT: Gravitational partition function and Out-of-time-order correlator
arXiv quant-ph
arXiv:2408.01538v4 Announce Type: replace-cross Abstract: In this paper, we compute the partition functions of $\mathcal{N}=1$ SUGRA for different boundary topologies, i.e. punctured sphere and torus, using super-Virasoro TQFT. We use…
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Nonlinear engineering of Hong-Ou-Mandel interference with structured light
arXiv quant-ph
arXiv:2609.33862v1 Announce Type: new Abstract: A pair of photons entering a Hong-Ou-Mandel interferometer will bunch or anti-bunch depending on the symmetry of their state in the measured degree of freedom, resulting in constructive or…
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Systematic errors from scalar slowing-down models in transient SERF magnetometry
arXiv quant-ph
arXiv:2609.31865v1 Announce Type: cross Abstract: Reduced Bloch models of spin-exchange-relaxation-free (SERF) magnetometers commonly describe the coupled electron--nuclear spin dynamics using a single nuclear slowing-down factor. We show…
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Efficient Quantum Fourier Transforms For Semisimple Algebras
arXiv quant-ph
arXiv:2605.05337v2 Announce Type: replace Abstract: The quantum Fourier transform (QFT) is a fundamental primitive in quantum computation and quantum information. In this work, we extend the framework for the QFT from finite groups to…
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Robust Entanglement Witnessing via Dense Network Coding with Graph States
arXiv quant-ph
arXiv:2609.32024v1 Announce Type: new Abstract: Practical tests for witnessing entanglement in the presence of noise are needed to verify and apply entanglement-based applications in real-world communication networks. Quantum dense network…
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Learning sparse quantum states from single-qubit measurements
arXiv quant-ph
arXiv:2609.35648v1 Announce Type: new Abstract: We study the problem of learning a sparse quantum state, an $n$-qubit quantum state whose density matrix has at most $s$ nonzero matrix entries in an unknown product basis. While such states…
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Generation of arbitrary quantum states in cavity-atom systems with a three-level ancilla
arXiv quant-ph
arXiv:2609.32845v1 Announce Type: new Abstract: We generalized the seminal work of Law & Eberly, and propose a protocol to generate arbitrary quantum states with a three-level atom as an ancilla in a more efficient manner. This protocol…
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Experimental quantum-computing-enhanced sensing using Grover's algorithm
arXiv quant-ph
arXiv:2609.35016v1 Announce Type: new Abstract: The combination of quantum sensing with quantum computing to provide an enhancement over conventional quantum sensing has recently emerged as a promising potential application of quantum…
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Zero Knowledge Proofs in Quantum Networks
arXiv quant-ph
arXiv:2609.35339v1 Announce Type: new Abstract: Zero-knowledge proofs (ZKPs) enable the verification of a statement without revealing any information beyond its validity and constitute a fundamental primitive in cryptography and…
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Dilation theorem for continuum quantum stochastic processes
arXiv quant-ph
arXiv:2609.35403v1 Announce Type: new Abstract: Connecting mathematical formalism in open quantum systems to its underlying physics necessitates the notion of a dilation, a way to bridge stochastic dynamics with deterministic Schr\"odinger…
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AG-CoT: Verified Algorithmic Traces for LLM Program Synthesis on Clifford Circuits
arXiv quant-ph
arXiv:2609.33192v1 Announce Type: cross Abstract: Scientific code generation can produce executable programs that fail to compute the intended scientific object. We study this problem in language-model synthesis of Clifford circuits, which…
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Enhanced entanglement from quantum ergodicity
arXiv quant-ph
arXiv:2507.08067v3 Announce Type: replace Abstract: The quantum chaos conjecture associates the spectral statistics of a quantum system with abstract notions of quantum ergodicity. Such associations are taken to be of fundamental and…
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Efficient Trotter-Suzuki Schemes for Long-time Quantum Dynamics
arXiv quant-ph
arXiv:2601.18756v3 Announce Type: replace Abstract: Accurately simulating long-time dynamics of many-body systems is a challenge in both classical and quantum computing due to the accumulation of Trotter errors. While low-order…
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Non-Markovian and non-Condon vibrationally assisted electron transfer in an effective ligand--receptor complex
arXiv quant-ph
arXiv:2602.06469v3 Announce Type: replace Abstract: We investigate vibrationally assisted electron transfer in an effective ligand--receptor complex using finite-temperature non-Markovian quantum-state diffusion with explicitly colored…
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Practical Limits to Single-Mode Vacuum Squeezing with a SNAIL Parametric Amplifier
arXiv quant-ph
arXiv:2603.14123v5 Announce Type: replace Abstract: We characterize single-mode vacuum squeezing generated by a SNAIL Parametric Amplifier (SPA) operated under conditions representative of practical sensing and qubit-readout experiments…
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Optically detected nuclear magnetic resonance of carbon-13 in bulk diamond
arXiv quant-ph
arXiv:2605.00152v3 Announce Type: replace Abstract: Precision measurements based on optically detected nuclear magnetic resonance offer exquisite sensitivity to absolute shifts in spin transition frequencies, with potential applications in…
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Sharp continuity of quantum conditional entropy
arXiv quant-ph
arXiv:2607.24687v2 Announce Type: replace Abstract: We prove the sharp uniform continuity bound for quantum conditional entropy. If two bipartite states are at trace distance at most $\delta$ and $d=\dim A$, the optimal dimension-only…
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Quantum-information fingerprints of partial dynamical symmetry in the interacting boson model
arXiv quant-ph
arXiv:2608.04486v2 Announce Type: replace Abstract: Partial dynamical symmetry (PDS) is an algebraic structure in which a prescribed symmetry is neither exact nor completely broken: a subset of eigenstates keeps good quantum numbers and…
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Sustained growth of quantum circuit complexity in many-body Hamiltonian dynamics
arXiv quant-ph
arXiv:2609.26885v2 Announce Type: replace Abstract: The quantum circuit complexity of an evolving many-body quantum system is believed to exhibit a sustained growth, maintained for timescales much longer than the onset of thermalization…
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SCORENF: Score-based Normalizing Flows for Sampling Unnormalized distributions
arXiv quant-ph
arXiv:2510.21330v2 Announce Type: replace-cross Abstract: Unnormalized probability distributions are central to modeling complex physical systems across various scientific domains. Traditional sampling methods, such as Markov Chain Monte…
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Metasurfaces for neutral-atom trapping
arXiv quant-ph
arXiv:2605.30498v3 Announce Type: replace-cross Abstract: Trapped neutral atoms are one of the leading platforms for quantum information technologies, in particular for quantum computing, but scaling them to array sizes needed for…
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Universal Quantum Transformer
arXiv quant-ph
arXiv:2606.00045v4 Announce Type: replace-cross Abstract: Classical continuous-space neural networks fundamentally struggle to lock into exact formal rules, whether mathematical, such as modular arithmetic and non-Abelian group algebra, or…
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Modular theory and affine representations on the Rindler horizon
arXiv quant-ph
arXiv:2606.01071v2 Announce Type: replace-cross Abstract: We develop a group-theoretic interpretation of the Unruh effect based on affine symmetry on a light ray and relate it to modular theory. For a massless scalar field in two spacetime…
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Embedding Paired Free-Fermion Gaussian States into Gutzwiller-Projected Bardeen--Cooper--Schrieffer Wave Functions
arXiv quant-ph
arXiv:2608.18168v2 Announce Type: replace-cross Abstract: Gutzwiller-projected Bardeen--Cooper--Schrieffer (BCS) wave functions of Abrikosov fermions are widely used to describe quantum many-body states. Taking the one-dimensional…
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Multivariable Painleve'-II equation: connection formulas for arbitrary system size
arXiv quant-ph
arXiv:2609.14996v2 Announce Type: replace-cross Abstract: Connection formulas for the asymptotic solutions of a system of n> 1 coupled Painleve'-II equations with symmetry-breaking parameters are written explicitly. An asymptotically exact…
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Quantum Encoding Agents: A Natural Language Interface for Data Embedding Strategy Selection in Quantum Machine Learning
arXiv quant-ph
arXiv:2609.31902v1 Announce Type: new Abstract: Selecting a data encoding is a central and poorly tooled decision in quantum machine learning. The feature map fixes the geometry of the Hilbert space, the expressibility of quantum kernels…
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Quantum Monte Carlo Tree Search with Fixed Confidence
arXiv quant-ph
arXiv:2609.33132v1 Announce Type: new Abstract: Recent advances in quantum computing are opening new opportunities for computationally intensive decision problems. This paper studies how quantum computing can improve Monte Carlo tree…
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Anyon Quasilocalization in a Quasicrystalline Toric Code
arXiv quant-ph
arXiv:2511.17144v3 Announce Type: replace-cross Abstract: An exactly solvable model of a quantum spin liquid on a quasicrystal, akin to Kitaev's honeycomb model, was introduced in Kim \textit{et al.}…
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Temporal trade-offs in high-dimensional entanglement: a comprehensive noise model for optimal time-bin QKD protocols
arXiv quant-ph
arXiv:2609.35488v1 Announce Type: new Abstract: High-dimensional time-bin entanglement is known for having high potential for quantum key distribution (QKD) applications, being easily implementable, robust and may offer better keyrates…
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Experimental Realization of the Markov Chain Monte Carlo Algorithm on a Quantum Computer
arXiv quant-ph
arXiv:2603.08395v4 Announce Type: replace Abstract: Quantum algorithms present a quadratically improved complexity over classical ones for certain sampling tasks. For instance, the Quantum Amplitude Estimation (QAE) algorithm promises to…
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Beyond NISQ Assumptions: One-time Memory in the Classically Accessible Random-Oracle Model
arXiv quant-ph
arXiv:2609.32603v1 Announce Type: new Abstract: Quantum information enables many cryptographic primitives that are impossible in the classical world. A line of works has developed cryptographic protocol under the assumption that quantum…
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Observation of a topological edge state among localized bulk states in the anisotropic quantum Rabi model
arXiv quant-ph
arXiv:2609.34332v1 Announce Type: new Abstract: Topological phases are governed by discrete symmetries that protect boundary modes against local perturbations. When translational periodicity is absent, the bulk states also become…
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Positronium Laser Deceleration, Cooling and Trapping
arXiv quant-ph
arXiv:2609.35202v1 Announce Type: new Abstract: We numerically study laser deceleration, cooling and trapping of host fast ortho-positronium (Ps) bunches as produced in silica microchannel targets using positron bunches from a Surko trap…
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Improving the Stability of the Hierarchical Equations of Motion for Open Quantum Systems with Strong Coupling to Structured Bosonic Baths
arXiv quant-ph
arXiv:2609.35484v1 Announce Type: new Abstract: The hierarchical equations of motion (HEOM) approach is one of the most powerful methods avail- able to simulate the dynamics of open quantum systems. Although the HEOM approach has been…
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Random access and high dimensional integrated quantum memory
arXiv quant-ph
arXiv:2508.19605v2 Announce Type: replace Abstract: Random-access quantum memory (RAQM) is a fundamental building block for scalable quantum networks and photonic quantum computing. While existing realizations rely on gaseous physical…
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Dynamical protection of quantum steering and fidelity dynamics in the double Jaynes-Cummings model
arXiv quant-ph
arXiv:2608.17217v2 Announce Type: replace Abstract: We investigate the dynamics of Einstein-Podolsky-Rosen (EPR) steering in a double Jaynes-Cummings model, where two initially entangled spatially separated two-level atoms in two cavities…
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Growth of quartet correlations in neutron-rich tellurium isotopes within quartet Bardeen-Cooper-Schrieffer theory
arXiv quant-ph
arXiv:2607.15700v3 Announce Type: replace-cross Abstract: Quartet correlations in neutron-rich Te isotopes are investigated within the quartet Bardeen-Cooper-Schrieffer (BCS) framework. Taking $^{100}$Sn as an inert core, we consider two…
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Cyclotomic Cosets: Hidden Subgroup and Quantum Sieving Algorithm for Prime-Power Moduli
arXiv quant-ph
arXiv:2609.34996v1 Announce Type: new Abstract: The Learning With Errors (LWE) problem is a fundamental assumption in post-quantum cryptography. Regev established a quantum reduction from LWE to the Dihedral Coset Problem (DCP). Later…
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Trainability of IQP Quantum Circuit Born Machines Under Gaussian Initialization
arXiv quant-ph
arXiv:2606.10179v3 Announce Type: replace Abstract: Quantum Circuit Born Machines (QCBMs) offer a natural approach to generative machine learning by leveraging the Born rule. Recent work has provided a method to classically train QCBMs…
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Measuring Clock Precision Without an Ideal Time Reference
arXiv quant-ph
arXiv:2609.31837v1 Announce Type: new Abstract: Characterising physical devices typically requires comparison with more precise reference standards. For clocks, however, this approach is problematic because no physically perfect time…
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Indefinite causal order with output-signalling instruments
arXiv quant-ph
arXiv:2609.31863v1 Announce Type: new Abstract: Quantum processes can exhibit indefinite causal order, allowing coherent superpositions of distinct orderings of events. Whether such processes generate genuinely noncausal statistics…
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Nonstabilizerness of the entangling layer in quantum circuit Born machines
arXiv quant-ph
arXiv:2609.32025v1 Announce Type: new Abstract: The entangling layer of a quantum circuit Born machine can supply both entanglement and nonstabilizerness. In this work we show that the entangling layer can be a Clifford circuit, which…
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Counterdiabatic quasi-Floquet control for the generation of entangled BICs using giant atoms
arXiv quant-ph
arXiv:2609.32125v1 Announce Type: new Abstract: Bound states in the continuum (BICs) provide a mechanism for preserving entanglement in waveguide quantum electrodynamics. Here, using quantum control techniques in a configuration of two…
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Conserved and relaxing modes enable polynomial-success coherent Carleman lattice Boltzmann evolution
arXiv quant-ph
arXiv:2609.32310v1 Announce Type: new Abstract: Carleman linearization represents nonlinear lattice Boltzmann collision dynamics in a form amenable to quantum block encoding, but low postselection probabilities in existing population-space…
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Feedback-based quantum optimization with low depth and measurement
arXiv quant-ph
arXiv:2609.32433v1 Announce Type: new Abstract: Feedback-based ALgorithm for Quantum OptimizatioN (FALQON) is a hybrid quantum-classical algorithm for solving combinatorial optimization problems, which circumvents classical parameter…
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An exponential strong converse for private communication over degradable quantum channels
arXiv quant-ph
arXiv:2609.32515v1 Announce Type: new Abstract: We prove an exponential strong converse for the unassisted private capacity of every finite-dimensional degradable quantum channel. We use a single error criterion: the infidelity between the…
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Stable Long-Range Charging and Boundary-Mediated Thresholds in a Waveguide Quantum Battery
arXiv quant-ph
arXiv:2609.32580v1 Announce Type: new Abstract: The waveguide-integrated architecture holds promise for scalable on-chip integration of a charger, a transmission channel, and a quantum battery in a modular, independently optimizable…
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How many photons can a molecule scatter before its coherence is lost?
arXiv quant-ph
arXiv:2609.33475v1 Announce Type: new Abstract: Molecular qubits held in conservative optical traps may lose coherence when they scatter photons from the trapping lasers. The rate for this process has two parts, one equal to the mean Raman…
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Engineering Defect-Phonon Interactions Through Heterophase-Interfaces in Silicon Carbide Membranes
arXiv quant-ph
arXiv:2609.33545v1 Announce Type: new Abstract: Point defects in wide-bandgap semiconductors offer spin and photonic qubits in a solid-state platform, making them important building blocks for quantum information processing, communication…
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Monotonicity of the R\'enyi channel capacity under non-signaling assisted channel simulation
arXiv quant-ph
arXiv:2609.34213v1 Announce Type: new Abstract: We ask whether non-signaling correlations shared between the sender and receiver can increase the R\'enyi capacity of a classical channel. Non-signaling boxes form a strictly larger class…
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Microsecond-Programmable Synthetic Quantum Matter: Circumventing the Adiabatic Bottleneck for Heisenberg-Limited Metrology
arXiv quant-ph
arXiv:2609.34559v1 Announce Type: new Abstract: Generating macroscopic quantum entanglement is central to quantum metrology. While traversing a quantum critical point yields Heisenberg-limited precision, adiabatic schemes are restricted by…
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Trotterisation Thresholds and Dissipative Quantum Chaos in Open-System Digital Quantum Simulation
arXiv quant-ph
arXiv:2609.34623v1 Announce Type: new Abstract: Digital quantum simulation (DQS) is one of the most promising applications of quantum computing. Trotterised DQS models quantum dynamics by decomposing the evolution into a sequence of…
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General Photon Subtraction from a Gaussian Perspective
arXiv quant-ph
arXiv:2609.34803v1 Announce Type: new Abstract: A near-deterministic source of non-Gaussianity is the missing piece to reach universal and fault-tolerant quantum computing with continuous-variable optics. Due to a lack of strong…
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Classical simulation of amplitude-damped bucket-brigade quantum random access memories via predictable branch evolution
arXiv quant-ph
arXiv:2609.34935v1 Announce Type: new Abstract: Classical simulation of quantum random access memory (QRAM) under noise can be accelerated dramatically by branch pruning: noise histories are sampled as trajectory ensembles, and good…
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Deployment of Large IQP Circuit Born Machines on Qubit-Limited Hardware Using Noise Injection
arXiv quant-ph
arXiv:2609.35163v1 Announce Type: new Abstract: Quantum circuit Born machines (QCBMs) built with instantaneous quantum polynomial (IQP) circuits have loss functions that can be efficiently estimated classically, but require quantum…
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Computational Complexity of Clifford Template Compilation: Are Quantum Computers Useful for Compiling Quantum Circuits?
arXiv quant-ph
arXiv:2609.35239v1 Announce Type: new Abstract: A Clifford template is a finite ordered family of repeatable Clifford operations, and an instantiation specifies how many times each operation is applied. The Clifford template compilation…
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An Exact Polynomial Task-Risk Bridge for Time-Multiplexed Photonic Quantum Reservoirs
arXiv quant-ph
arXiv:2609.35243v1 Announce Type: new Abstract: Time-multiplexed (TDM) photonic reservoirs are usually judged by their scores on a few datasets, which say little about a chip's overall performance, and designed by enumerating candidate…
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Gauge freedom and efficient algorithms for Lindbladian learning
arXiv quant-ph
arXiv:2609.35265v1 Announce Type: new Abstract: We study the problem of learning a local Lindbladian in the presence of state-preparation-and-measurement (SPAM) noise. Although recent work has developed scalable learning algorithms under…
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Distributional Variants of the Aaronson-Ambainis Conjecture
arXiv quant-ph
arXiv:2609.35327v1 Announce Type: new Abstract: A longstanding conjecture in quantum complexity theory asserts that, under the uniform input distribution, quantum query algorithms can be polynomially simulated by classical query…
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Heuristic lower bounds on real Grothendieck constants of finite and infinite order
arXiv quant-ph
arXiv:2609.35399v1 Announce Type: new Abstract: We propose candidate lower bounds on the real Grothendieck constants $K_{\mathrm G}(d)$ and their infinite-dimensional limit $K_{\mathrm G}$ using rotationally invariant cubic kernels. For…
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Fixed-Time Gaussian State Transfer via Collective Dissipation in a Fully Static Architecture
arXiv quant-ph
arXiv:2609.35446v1 Announce Type: new Abstract: We establish a fully static, dissipation-only primitive for Gaussian state transfer in which collective coupling to a shared environment fixes a single transfer time without coherent…
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Induced Coherence in Quantum and Classical Interferometry: Origin and Control
arXiv quant-ph
arXiv:2609.35523v1 Announce Type: new Abstract: The wave-particle duality that manifests in the Young's double-slit interferometry satisfying the well known Englert-Greenberger-Yasin inequality has recently been shown to obey a universal…
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Quantum Query Complexity Beyond the Worst Case
arXiv quant-ph
arXiv:2609.35580v1 Announce Type: new Abstract: Smoothed analysis is a central framework in classical algorithms for explaining the performance of algorithms beyond the worst case, often explaining why algorithms perform well in practice…
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QC-Stark: A Multi-Task Benchmark Revealing Capability Dissociations in LLMs Evaluated on Quantum Computing Tasks
arXiv quant-ph
arXiv:2609.35581v1 Announce Type: new Abstract: We introduce QC-Stark, a benchmark for evaluating large language models (LLMs) on 11 quantum computing (QC) tasks, spanning circuit construction, debugging, compilation, error correction, and…
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Succinct Arguments for QMA from Collapsing Hash Functions
arXiv quant-ph
arXiv:2609.35633v1 Announce Type: new Abstract: We prove the existence of succinct arguments for QMA, assuming only the existence of collapsing hash functions. This is the first scheme that relies only on unstructured ``Minicrypt''…
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Optimal performance in a chaotic Floquet quantum battery
arXiv quant-ph
arXiv:2609.35655v1 Announce Type: new Abstract: We study a quantum battery consisting of $N$ qubits interacting uniformly with each other. Starting from its ground state, the battery is charged by introducing periodic kicks in the…
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An Optimal Quantum Linear Systems Algorithm
arXiv quant-ph
arXiv:2609.35660v1 Announce Type: new Abstract: In the quantum linear systems problem (QLSP), we are given query access to a $d$-sparse $N\times N$ matrix $A$ with condition number $\kappa$, and the ability to prepare a quantum state…
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Analytic detector responses and entanglement in constant-curvature spacetimes
arXiv quant-ph
arXiv:2609.29992v1 Announce Type: cross Abstract: We derive analytic response functions for Unruh--DeWitt detectors coupled to real, massless, conformally coupled scalar fields, to distinguish the effects of the field spectrum and global…
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Reduced scaling implementation of the coupled cluster-based static embedding method, MPCC with density fitting
arXiv quant-ph
arXiv:2609.32884v1 Announce Type: cross Abstract: An improved algorithm to implement our previously proposed static quantum embedding method MPCC (J. Chem. Phys. 161, 164107 (2024)) is presented. It uses the density-fitting (DF)…
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Apparent Compression, Real Stability: The Intrinsic Dimension of Learning a Quantum Wavefunction
arXiv quant-ph
arXiv:2609.33193v1 Announce Type: cross Abstract: How many directions in weight space does training need? The intrinsic dimension answers this with the smallest number of random directions in which training still reaches a target accuracy…
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Effective atom-dimer bands of three-body lattice systems at strong coupling: exact critical mass ratios and a statistics-quasimomentum duality
arXiv quant-ph
arXiv:2609.33576v1 Announce Type: cross Abstract: We study three particles on the square lattice with contact interactions of infinite strength, for all total quasimomenta, for three statistics: three identical bosons, two identical…
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The equivalence of topological indices for $\mathrm{U}(1)\rtimes\mathbb{Z}_2$-symmetric quantum spin chains
arXiv quant-ph
arXiv:2609.34119v1 Announce Type: cross Abstract: Symmetry-protected topological (SPT) phases in quantum spin chains are distinguished by topological indices. Ogata's operator-algebraic indices apply to a broad range of symmetry classes…
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Bounding Retraining Equivalence and the Deletion Floor in Materials Machine Unlearning
arXiv quant-ph
arXiv:2609.35635v1 Announce Type: cross Abstract: In materials machine learning, closely related retained structures can sustain accurate property predictions even after removing a specific record, rendering post-deletion prediction error…
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Robust Non-Adiabatic Holonomic Gating in Qutrits via Inverse-Engineered Pulse Shaping and Error Compensation
arXiv quant-ph
arXiv:2510.05905v4 Announce Type: replace Abstract: Systematic Rabi-amplitude and detuning errors remain important sources of infidelity in high-fidelity quantum gates. We develop a robust pulse-engineering scheme for non-adiabatic…
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Anticoncentration is (almost) all you need
arXiv quant-ph
arXiv:2510.23719v4 Announce Type: replace Abstract: Until very recently, it was generally believed that the (approximate) 2-design property is strictly stronger than anticoncentration of random quantum circuits, mainly because it was shown…
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The strong converse exponent of composable randomness extraction against quantum side information
arXiv quant-ph
arXiv:2601.19182v2 Announce Type: replace Abstract: We find a tight characterization of the strong converse exponent for randomness extraction against quantum side information. In contrast to previous tight bounds, we employ a composable…
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Monte Carlo sampling from a projected entangled-pair state in simulations of quantum annealing in the three dimensional random Ising model
arXiv quant-ph
arXiv:2603.16509v2 Announce Type: replace Abstract: Quantum annealing with the D-Wave Advantage system in the random Ising model on a cubic lattice is simulated using a three-dimensional (3D) tensor network. The Hamiltonian is driven…
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On Non-Existence of Absolutely Maximally Entangled Canonical Graph States in Even Local Dimensions
arXiv quant-ph
arXiv:2603.18193v3 Announce Type: replace Abstract: We demonstrate that absolutely maximally entangled (AME) states consisting of $N=4n$ qudits with $n\in\{1,2,3,\ldots\}$, each of even local dimension $d$, cannot be realized as canonical…
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Nonperturbative Resummation of Divergent Time-Local Generators: Disentangling Non-Markovian Dynamics
arXiv quant-ph
arXiv:2603.25512v3 Announce Type: replace Abstract: Perturbative van Kampen cumulant expansions of time-local generators of open quantum systems generically diverge at long times, but the reduced dynamics is regular. We show that the…
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Local state antimarking : Nonlocality without entanglement
arXiv quant-ph
arXiv:2605.09710v2 Announce Type: replace Abstract: A set of quantum states is said to be antidistinguishable if, upon being given a randomly chosen state from the set, it is possible to exclude with certainty a state that was definitely…
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Transition-state lattice modes and the breakdown of adiabatic tunneling for hydrogen and deuterium in bcc Nb
arXiv quant-ph
arXiv:2605.23212v2 Announce Type: replace Abstract: Interstitial hydrogen and deuterium in body-centered-cubic metals constitute archetypal quantum tunneling systems. Their relevance has been renewed by the connection between hydrogenic…
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Improved GKP magic states from error-corrected non-Gaussian quantum states
arXiv quant-ph
arXiv:2607.07833v2 Announce Type: replace Abstract: Gate teleportation, together with magic state distillation, is a promising route towards fault-tolerant, universal computation. In the context of bosonic quantum computation, Baragiola et…
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QUBO Sampling for Mixed Binary Quadratic Programming without Continuous Variable Binarization
arXiv quant-ph
arXiv:2607.21286v2 Announce Type: replace Abstract: Quantum annealing and related combinatorial optimization methods typically accept quadratic unconstrained binary optimization (QUBO) problems as input, whereas many practical models…
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The bare necessities of a physically reasonable mathematical model for quantum theory
arXiv quant-ph
arXiv:2607.24474v2 Announce Type: replace Abstract: What are the minimal requirements for a physically reasonable mathematical model for quantum theory or a potential extension? In addressing this question, rather than relying on the…
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Immittance formulas for exact blackbox quantization and divergence-free effective models in circuit QED
arXiv quant-ph
arXiv:2608.26027v2 Announce Type: replace Abstract: Building on the first-order circuit quantization method [arXiv:2304.12252, arXiv:2401.09120], we provide simple formulas to construct exact Hamiltonians for Josephson-junction-based…
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A Quantum Framework for K Coloring of Graphs
arXiv quant-ph
arXiv:2609.32348v1 Announce Type: new Abstract: Graph coloring is a well-known NP-complete problem with applications in scheduling, register allocation, frequency assignment, and network optimization. Quantum computing offers the potential…
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Efficient Simulation of Hybrid Continuous- and Discrete-Variable Quantum Circuits via Gaussian Decompositions
arXiv quant-ph
arXiv:2609.34793v1 Announce Type: new Abstract: Hybrid quantum systems combining discrete-variable (DV) and continuous-variable (CV) subsystems arise across a broad range of physical platforms and enable quantum information processing…
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Fabrication-free assessment of microwave losses in germanium-based dielectrics and superconductors
arXiv quant-ph
arXiv:2608.28463v2 Announce Type: replace Abstract: We present a flip-chip-based sensing scheme to measure effective microwave losses associated with target materials for quantum technologies, without requiring any device fabrication on…
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Analytical diagonalization of the open-boundary bosonic Kitaev chain: An asymmetric plane-wave ansatz approach
arXiv quant-ph
arXiv:2608.29684v2 Announce Type: replace Abstract: The bosonic Kitaev chain under open boundary conditions has attracted recent attention due to its realization in driven-dissipative systems and its intriguing non-Hermitian boundary…
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From Reversible Quantum Dynamics to Statistical Probability: A dynamical solution to the origin of probability and Hilbert's sixth problem
arXiv quant-ph
arXiv:2609.18593v2 Announce Type: replace Abstract: Hilbert's sixth problem placed probability and mechanics at the center of the axiomatization of physics. It asks how irreversible statistical probability and thermodynamics can follow…
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On the Born rule in a new quantum approach
arXiv quant-ph
arXiv:2609.24269v3 Announce Type: replace Abstract: In the context of a new approach towards quantum foundation, the Born rule is proved under a weak condition through several steps. The sole weak condition behind the Born rule is called…
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Residual Fisher Information in Measurement-Error Uncertainty
arXiv quant-ph
arXiv:2609.31311v2 Announce Type: replace Abstract: Measurement error in the Watanabe-Sagawa-Ueda formulation is the excess estimation error of a classical record over the quantum statistical limit. We show that, at the quantum-instrument…
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Coherence of a hole spin flopping-mode qubit in a circuit quantum electrodynamics environment
arXiv quant-ph
arXiv:2503.10788v2 Announce Type: replace-cross Abstract: The entanglement of microwave photons and spin qubits in silicon represents a pivotal step forward for quantum information processing utilizing semiconductor quantum dots. Such…
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Long-lived giant circular Rydberg atoms at room temperature
arXiv quant-ph
arXiv:2510.27471v3 Announce Type: replace-cross Abstract: Stability achieved by large angular momentum is ubiquitous in nature, with examples ranging from classical mechanics, over optics and chemistry, to nuclear physics. In atoms…
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Rational degree is polynomially related to degree
arXiv quant-ph
arXiv:2601.08727v3 Announce Type: replace-cross Abstract: We prove that $\mathrm{deg}(f) \leq \widetilde{O}(\mathrm{rdeg}(f)^3)$ for every Boolean function $f$, where $\mathrm{deg}(f)$ is the degree of $f$ and $\mathrm{rdeg}(f)$ is the…