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We demonstrate how to discriminate two non-orthogonal, entangled quantum state which are slightly different from each other by using pseudo-Hermitian system. The positive definite metric operator which makes the pseudo-Hermitian systems…

Quantum Physics · Physics 2015-06-04 Ananya Ghatak , Bhabani Prasad Mandal

Non-Hermitian topological edge states have many intriguing properties, but have so far mainly been discussed in terms of bulk-boundary correspondence. Here we propose to use a bulk property of diffusion coefficients for probing the…

Quantum Physics · Physics 2022-01-25 Zhiyu Tian , Yang Liu , Le Luo

Viewing a quantum thermal machine as a non-Hermitian quantum system, we characterize in full generality its analytical time-dependent dynamics by deriving the spectrum of its non-Hermitian Liouvillian for an arbitrary initial state. We show…

Quantum Physics · Physics 2021-12-14 Shishir Khandelwal , Nicolas Brunner , Géraldine Haack

We develop a unified quantum geometric framework to understand reactive quantum dynamics. The critical roles of the quantum geometry of adiabatic electronic states in both adiabatic and non-adiabatic quantum dynamics are unveiled. A…

Chemical Physics · Physics 2025-05-19 Yujuan Xie , Ruoxi Liu , Bing Gu

Biphoton process is an essential benchmark for quantum information science and technologies, while great efforts have been made to improve the coherence of the system for better quantum correlations. Nevertheless, we find that the…

Quantum Physics · Physics 2023-12-01 Kangkang Li , Yin Cai , Jin Yan , Zhou Feng , Fu Liu , Lei Zhang , Feng Li , Yanpeng Zhang

We present a theoretical study of quantum phases and quantum phase transitions occurring in non-Hermitian $\mathcal{P}\mathcal{T}$-symmetric superconducting qubits chains described by a transverse-field Ising spin model. A non-Hermitian…

Quantum Physics · Physics 2023-08-15 Grigory A. Starkov , Mikhail V. Fistoul , Ilya M. Eremin

We review some recent work on the occurrence of coalescing eigenstates at exceptional points in non-Hermitian systems and their influence on physical quantities. We particularly focus on quantum dynamics near exceptional points in open…

Quantum Physics · Physics 2021-10-27 Savannah Garmon , Takafumi Sawada , Kenichi Noba , Gonzalo Ordonez

This paper reports on the experimental observation of topologically protected edge state and exceptional point in an open and Non-Hermitian system. While the theoretical underpinning is generic to wave physics, the simulations and…

Mesoscale and Nanoscale Physics · Physics 2018-09-26 Weiwei Zhu , Xinsheng Fang , Dongting Li , Yong Sun , Yong Li , Yun Jing , Hong Chen

The behavior of quantum states at exceptional points and at critical points associated with quantum phase transitions is intriguing yet puzzling. In this study, we present an alternative method for obtaining the Berry potentials using the…

Quantum Physics · Physics 2025-11-18 Chia-Yi Ju , Fu-Hsiang Huang

Understanding molecular state evolution is central to many disciplines, including molecular dynamics, precision measurement, and molecule-based quantum technology. Details of the evolution are obscured when observing a statistical ensemble…

Atomic Physics · Physics 2024-08-05 Yu Liu , Julian Schmidt , Zhimin Liu , David R. Leibrandt , Dietrich Leibfried , Chin-wen Chou

In this paper, we describe some interesting properties of a non-Hermitian Jaynes-Cummings model. For this particular model, it is known that the Hilbert space can be described by infinitely-many two-dimensional invariant (closed) subspaces,…

Quantum Physics · Physics 2026-04-23 Gargi Das , Aritra Ghosh , Bhabani Prasad Mandal

Topological quantum states are characterized by nonlocal invariants, and their detection is intrinsically challenging. Various strategies have been developed to study topological Hamiltonians through their equilibrium states. We present a…

The phenomenon of quantum phase transition is considered in the special case in which the evolution laws remain unitary and in which the bound-state energies remain observable. The conventional Hermiticity of observables is lost at the…

Quantum Physics · Physics 2018-04-24 Miloslav Znojil

The accurate simulation of real--time quantum transport is notoriously difficult, requiring a consistent scheme to treat incoming and outgoing fluxes at the boundary of an open system. We demonstrate a method to converge non--equilibrium…

Mesoscale and Nanoscale Physics · Physics 2015-10-02 Justin E. Elenewski , Yanxiang Zhao , Hanning Chen

We study quantum circuits consisting of unitary gates, projective measurements, and control operations that steer the system towards a pure absorbing state. Two types of phase transition occur as the rate of these control operations is…

Quantum Physics · Physics 2023-06-07 Lorenzo Piroli , Yaodong Li , Romain Vasseur , Adam Nahum

The state of a quantum system may be steered towards a predesignated target state, employing a sequence of weak $\textit{blind}$ measurements (where the detector's readouts are traced out). Here we analyze the steering of a two-level system…

Quantum Physics · Physics 2022-01-19 Parveen Kumar , Kyrylo Snizhko , Yuval Gefen , Bernd Rosenow

The method of quantum tomography, which allows us to track with high accuracy the evolution of multilevel quantum systems (qudits) in Hilbert spaces of various dimensions is presented. The developed algorithms for quantum control are based…

Quantum Physics · Physics 2022-01-12 Yu. I. Bogdanov , N. A. Bogdanova , Yu. A. Kuznetsov , V. F. Lukichev

Exceptional points are the branch-point singularities of non-Hermitian Hamiltonians, and have rich consequences in open-system dynamics. While the exceptional points and their critical phenomena are widely studied in the non-Hermitian…

Quantum Physics · Physics 2024-08-22 Konghao Sun , Wei Yi

We demonstrate that the non-Hermitian quantum geometric tensor (QGT) governs nonlinear electrical responses in systems with a spectral line gap. The quantum metric, which is the symmetric component of the QGT and takes complex values in…

Mesoscale and Nanoscale Physics · Physics 2026-03-24 Kai Chen , Jie Zhu

Exceptional points facilitate peculiar dynamics in non-Hermitian systems. Yet, in photonics, they have mainly been studied in the classical realm. In this work, we reveal the behavior of two-photon quantum states in non-Hermitian systems…