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Papers

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

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12,932 papers in 12 months (-5% vs prior quarter)

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583 papers found

Variational quantum algorithm for generalized eigenvalue problems of non-Hermitian systems

Jiaxin Li, Zhaobing Fan, Hongmei Yao +5 more·Jul 7, 2025

Non-Hermitian generalized eigenvalue problems (GEPs) play a significant role in many practical applications, such as mechanical engineering. Based on the generalized Schur decomposition, we propose a variational quantum algorithm for solving the GEPs...

Quantum Physics

Physics and computation: An insight from non-Hermitian quantum computing

Qi Zhang, Biao Wu·Jun 22, 2025

We elucidate the profound connection between physics and computation by proposing and examining the model of the non-Hermitian quantum computer (NQC). In addition to conventional quantum gates such as the Hadamard, phase, and CNOT gates, this model i...

Quantum Physics

Operator-space fragmentation and integrability in Pauli-Lindblad models

Dawid Paszko, Christopher J. Turner, Dominic C. Rose +1 more·Jun 20, 2025

The Lindblad equation for open quantum systems is central to our understanding of coherence and entanglement in the presence of Markovian dissipation. In closed quantum systems Hilbert-space fragmentation is an effective mechanism for slowing decoher...

Physics

Observation of Criticality-Enhanced Quantum Sensing in Nonunitary Quantum Walks

Lei Xiao, Saubhik Sarkar, Kunkun Wang +2 more·Jun 19, 2025

Quantum physics enables parameter estimation with precisions beyond the capability of classical sensors. Quantum criticality is a key resource for this quantum-enhanced sensing, but experimental realization has been challenging due to the complexity ...

Quantum Physics

A Hierarchy of Deviation from Complete Positivity and Optimal Entanglement Witnesses

Mohsen Kian·Jun 4, 2025

We introduce the \emph{CP-distance} to quantify the deviation of Hermitian linear maps from complete positivity, defined as the minimal depolarizing noise required to render a map completely positive. We derive a closed spectral formula for this dist...

Quantum Physicsmath.FA

Computational Complexity and Simulability of Non-Hermitian Quantum Dynamics

Brian Barch, Daniel Lidar·Jun 3, 2025

Non-Hermitian (NH) quantum systems demonstrate striking differences from their Hermitian counterparts, leading to claims of NH advantage in areas ranging from metrology to entanglement generation. We show that in the context of quantum computation, a...

Quantum PhysicsComplexity

Quantum harmonic oscillator, index theorem and spectral asymmetry

Shunrui Li, Yang Liu·May 27, 2025

We report a spectral asymmetry effect in the quantum harmonic oscillator, where its partition function is identified as the Chern character. This establishes a direct link between statistical mechanics, and topological invariants (Atiyah-Singer index...

Quantum Physicshep-thMathematical Physics

A Variational Quantum Eigensolver Based on the Measurement Scheme Tailored to Multiband Tight-Binding Simulations

Dongkeun Lee, Hoon Ryu·May 23, 2025

We propose a cost-efficient measurement scheme of the variational quantum eigensolver (VQE) for atomistic simulations of electronic structures based on a tight-binding (TB) theory. Leveraging the lattice geometry of a material domain, the sparse TB H...

MedicinePhysics

$\mathcal{PT-}$Symmetric Open Quantum Systems: Information Theoretic Facets

Baibhab Bose, Devvrat Tiwari, Subhashish Banerjee·May 22, 2025

The theory of an $η$-pseudo Hermitian Hamiltonian with $\mathcal{PT}$ symmetry is reviewed and extended to include open system dynamics. A first-principles derivation of the generalized Gorini-Kossakowski-Sudarshan-Lindblad master equation appropriat...

Quantum Physicshep-th

Variational Quantum Algorithm for Solving the Liouvillian Gap

Xu-Dan 旭丹 Xie 谢, Zheng-Yuan 正远 Xue 薛, Dan-Bo 旦波 Zhang 张·May 22, 2025

In open quantum systems, the Liouvillian gap characterizes the relaxation time toward the steady state. However, accurately computing this quantity is notoriously difficult due to the exponential growth of the Hilbert space and the non-Hermitian natu...

Physics

Circuit structure-preserving error mitigation for High-Fidelity Quantum Simulations

Ruizhe Shen, Tianqi Chen, Ching Hua Lee·May 22, 2025

Developing methods to accurately characterize and mitigate the impact of noise is crucial for enhancing the fidelity of quantum simulations on Noisy Intermediate-Scale Quantum (NISQ) devices. In this work, we present a circuit structure-preserving er...

Physics

NonHermitian Topological Phases in a Hermitian Modified Bosonic Kitaev Chain

Raditya Weda Bomantara, Ibsal Assi, J. P. F. LeBlanc +1 more·May 21, 2025

We present a modification to the bosonic Kitaev chain that, despite being Hermitian, supports both nonHermitian skin effect and nontrivial topological edge modes in its excitation Hamiltonian. We establish an exact mapping between the excitation Hami...

Quantum Physics

Learning to Program Quantum Measurements for Machine Learning

S. Y. Chen, H. Tseng, Hsin-Yi Lin +1 more·May 18, 2025

The rapid advancements in quantum computing (QC) and machine learning (ML) have sparked significant interest, driving extensive exploration of quantum machine learning (QML) algorithms to address a wide range of complex challenges. The development of...

Computer SciencePhysics

Zassenhaus Expansion in Solving the Schr\"odinger Equation

Molena Nguyen, Naihuan Jing·May 14, 2025

Hamiltonian simulation is a central task in quantum computing, with wide-ranging applications in quantum chemistry, condensed matter physics, and combinatorial optimization. A fundamental challenge lies in approximating the unitary evolution operator...

Physics

Emergence of Hermitian topology from non-Hermitian knots

Gaurav Hajong, Ranjan Modak, Bhabani Prasad Mandal·Apr 28, 2025

The non-Hermiticity of the system gives rise to a distinct knot topology in the complex eigenvalue spectrum, which has no counterpart in Hermitian systems. In contrast, the singular values of a non-Hermitian (NH) Hamiltonian are always real by defini...

Quantum PhysicsMesoscale Physicshep-thMathematical Physics

Spin-Depairing-Induced Exceptional Fermionic Superfluidity

Soma Takemori, Kazuki Yamamoto, Akihisa Koga·Apr 28, 2025

We investigate the non-Hermitian (NH) attractive Hubbard model with spin depairing, which is a spin-resolved asymmetric hopping that nonreciprocally operates spins in the opposite direction. We find that spin depairing stabilizes a superfluid state u...

cond-mat.quant-gascond-mat.stat-mechcond-mat.str-elcond-mat.supr-con

Hopf Exceptional Points

Tsuneya Yoshida, Emil J. Bergholtz, Tomáš Bzdušek·Apr 17, 2025

Exceptional points at which eigenvalues and eigenvectors of non-Hermitian matrices coalesce are ubiquitous in the description of a wide range of platforms from photonic or mechanical metamaterials to open quantum systems. Here, we introduce a class o...

Mesoscale Physicsphysics.opticsQuantum Physics

Quantum simulations of nuclear resonances with variational methods

A. Singh, P. Siwach, P. Arumugam·Apr 16, 2025

The many-body nature of nuclear physics problems poses significant computational challenges. These challenges become even more pronounced when studying the resonance states of nuclear systems, which are governed by the non-Hermitian Hamiltonian. Quan...

Physics

Work Statistics and Quantum Trajectories: No-Click Limit and non-Hermitian Hamiltonians

Manali Malakar, Alessandro Silva·Apr 15, 2025

We investigate quantum work statistics within the standard two-point measurement (TPM) scheme in continuously monitored quantum systems, including the effects of generalized unitary evolution, possibly controlled by quantum circuit models, and multip...

Quantum Physicscond-mat.stat-mech

Non-Hermitian Multipole Skin Effects Challenge Localization

Jacopo Gliozzi, Federico Balducci, Taylor L. Hughes +1 more·Apr 14, 2025

We study the effect of quenched disorder on the non-Hermitian skin effect in systems that conserve a U(1) charge and its associated multipole moments. In particular, we generalize the Hatano-Nelson argument for a localization transition in disordered...

cond-mat.dis-nnMesoscale Physicscond-mat.str-elQuantum Physics
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