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Papers

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

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12,593 papers in 12 months (-14% vs prior quarter)

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564 papers found

Koopman Nonlinear Non-Hermitian Skin Effect

Shu Hamanaka·Jan 7, 2026

Non-Hermitian skin effects are conventionally manifested as boundary localization of eigenstates in linear systems. In nonlinear settings, however, where eigenstates are no longer well defined, it becomes unclear how skin effects should be faithfully...

Mesoscale Physicscond-mat.stat-mechQuantum Physics

Local Scale Invariance in Quantum Theory: A Non-Hermitian Pilot-Wave Formulation

Indrajit Sen, Matthew Leifer·Jan 7, 2026

We show that Weyl's abandoned idea of local scale invariance has a natural realization at the quantum level in pilot-wave (de Broglie-Bohm) theory. We obtain the Weyl covariant derivative by complexifying the electromagnetic gauge coupling parameter....

Quantum Physicsgr-qchep-thphysics.hist-ph

Entanglement signatures of quantum criticality in Floquet non-Hermitian topological systems

Siyuan Cheng, Rui Xie, Xiaosen Yang +2 more·Jan 6, 2026

The entanglement entropy can be an effective diagnostic tool for probing topological phase transitions. In one-dimensional single particle systems, the periodic driving generates a variety of topological phases and edge modes. In this work, we invest...

Quantum PhysicsMesoscale Physics

Stable boundary modes for fragile topology from spontaneous PT-symmetry breaking

Kang Yang, Fei Song, Piet W. Brouwer·Jan 6, 2026

Two-dimensional topological insulators protected by nonlocal symmetries or with fragile topology usually do not admit robust in-gap edge modes due to the incompatibility between the symmetry and the boundary. Here, we show that in a parity-time (PT) ...

Mesoscale Physicsphysics.opticsQuantum Physics

Asymptotic freedom, lost: Complex conformal field theory in the two-dimensional $O(N>2)$ nonlinear sigma model and its realization in Heisenberg spin chains

Christopher Yang, Thomas Scaffidi·Jan 5, 2026

The two-dimensional $O(N)$ nonlinear sigma model (NLSM) is asymptotically free for $N>2$: it exhibits neither a nontrivial fixed point nor spontaneous symmetry-breaking. Here we show that a nontrivial fixed point generically does exist in the complex...

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

Non-Hermitian second-order topological insulator with point gap

Xue-Min Yang, Hao Lin, Jian Li +3 more·Jan 4, 2026

The zero-mode corner states in the gap of two-dimensional non-Hermitian Su-Schrieffer-Heeger model are robust to infinitesimal perturbations that preserve chiral symmetry. However, we demonstrate that this general belief is no longer valid in large-s...

Quantum Physics

Implicitly Restarted Lanczos Enables Chemically-Accurate Shallow Neural Quantum States

Wei Liu, Wenjie Dou·Jan 4, 2026

The variational optimization of high-dimensional neural network models, such as those used in neural quantum states (NQS), presents a significant challenge in machine intelligence. Conventional first-order stochastic methods (e.g., Adam) are plagued ...

Quantum Physicsphysics.chem-ph

Symmetry and Topology in the Non-Hermitian Kitaev chain

Ayush Raj, Soham Ray, Sai Satyam Samal·Jan 2, 2026

We investigate the non-Hermitian Kitaev chain with non-reciprocal hopping amplitudes and asymmetric superconducting pairing. We work out the symmetry structure of the model and show that particle-hole symmetry (PHS) is preserved throughout the entire...

Mesoscale Physicscond-mat.stat-mechQuantum Physics

Pseudo-Hermitian Magnon Dynamics

Jamal Berakdar, Xi-guang Wang·Jan 2, 2026

A defining quantity of a physical system is its energy which is represented by the Hamiltonian. In closed quantum mechanical or/and coherent wave-based systems the Hamiltonian is introduced as a Hermitian operator which ensures real energy spectrum a...

Mesoscale Physicscond-mat.mtrl-sciphysics.opticsQuantum Physics

Non-Hermitian Band Topology and Edge States in Atomic Lattices

Wenxuan Xie, John C Schotland·Jan 1, 2026

We investigate the band structure and topological phases of one- and two-dimensional bipartite atomic lattices mediated by long-range dissipative radiative coupling. By deriving an effective non-Hermitian Hamiltonian for the single-excitation sector,...

Quantum Physicsphysics.optics

Lindbladian PT phase transitions

Yuma Nakanishi, Tomohiro Sasamoto·Dec 31, 2025

A parity-time (PT) transition is a spectral transition characteristic of non-Hermitian generators; it typically occurs at an exceptional point, where multiple eigenvectors coalesce. The concept of a PT transition has been extended to Markovian open q...

Quantum Physics

Geometric phase of exceptional point as quantum resonance in complex scaling method

Okuto Morikawa, Shoya Ogawa, Soma Onoda·Dec 31, 2025

Non-Hermitian operators and exceptional points (EPs) are now routinely realized in few-mode systems such as optical resonators and superconducting qubits. However, their foundations in genuine scattering problems with unbounded Hamiltonians remain mu...

Quantum Physicshep-thnucl-th

Uncertainty inequalities in a non-Hermitian scenario: the problem of the metric

Yanet Alvarez, Mariela Portesi, Romina Ramirez +1 more·Dec 30, 2025

We investigate uncertainty relations for quantum observables evolving under non-Hermitian Hamiltonians, with particular emphasis on the role of metric operators. By constructing appropriate metrics in each dynamical regime, namely the unbroken-symmet...

Quantum Physics

Dissipation-Stabilized Quantum Revivals in a Non-Hermitian Lattice Gauge Theory

Yevgeny Bar Lev, Jad C. Halimeh, Achilleas Lazarides·Dec 30, 2025

With the advent of quantum simulation experiments of lattice gauge theories (LGTs), an open question is the effect of non-Hermiticity on their rich physics. The well-known PXP model, a U$(1)$ LGT with a two-level electric field in one spatial dimensi...

Quantum Physicscond-mat.quant-gascond-mat.stat-mechcond-mat.str-el

Entanglement dynamics driven by topology and non-Hermiticity

Li-Wei Wang, Bolun Hu, Haixiao Zhang +3 more·Dec 30, 2025

The interplay between topology and non-Hermiticity gives rise to exotic dynamic phenomena that challenge conventional wave-packet propagation and entanglement dynamics. While recent studies have established the non-Hermitian skin effect (NHSE) as a k...

physics.opticsMesoscale PhysicsQuantum Physics

Quantum Speed Limits Based on the Sharma-Mittal Entropy

Dong-Ping Xuan, Zhi-Xi Wang, Shao-Ming Fei·Dec 30, 2025

Quantum speed limits (QSLs) establish intrinsic bounds on the minimum time required for the evolution of quantum systems. We present a class of QSLs formulated in terms of the two-parameter Sharma-Mittal entropy (SME), applicable to finite-dimensiona...

Quantum Physics

Exploring Spectral Singularities and Topological Lasers in PT-Symmetric Weyl Semimetals

Arda Sevinc, Rama Alassadi, Mustafa Sarisaman·Dec 30, 2025

This paper investigates the unique properties of PT-symmetric Topological Weyl Semimetals (TWS) within the framework of non-Hermitian physics, focusing on their potential for generating topological lasers. By exploring the role of spectral singularit...

physics.opticscond-mat.mtrl-sciQuantum Physics

Non-Hermitian higher-order topological insulators enabled by altermagnet engineering

Xiang Ji, Dengfeng Wang, Tong Zhou +1 more·Dec 30, 2025

We show that proximity to an altermagnet provides an efficient route to engineering non-Hermitian higher-order topological phases. The proximity-induced altermagnetic order gaps the edge states of a topological insulator, thereby driving a transition...

Mesoscale PhysicsQuantum Physics

Quantum Geometric Bounds in Non-Hermitian Systems

Milosz Matraszek, Wojciech J. Jankowski, Jan Behrends·Dec 29, 2025

We identify quantum geometric bounds for observables in non-Hermitian systems. We find unique bounds on non-Hermitian quantum geometric tensors, generalized two-point response correlators, conductivity tensors, and optical weights. We showcase these ...

Quantum PhysicsMesoscale Physicsphysics.optics

Generalised Entanglement Entropies from Unit-Invariant Singular Value Decomposition

Pawel Caputa, Abhigyan Saha, Piotr Sułkowski·Dec 28, 2025

We introduce generalisations of von Neumann entanglement entropy that are invariant with respect to certain scale transformations. These constructions are based on the Unit-Invariant Singular Value Decomposition (UISVD) in its left-, right-, and bi-i...

hep-thMathematical Physicsmath.PRQuantum Physics
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