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Related papers: Observables in non-Hermitian systems: A methodolog…

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Non-Hermitian physics predicts open quantum system dynamics with unique topological features such as exceptional points and the non-Hermitian skin effect. We show that this new paradigm of topological systems can serve as probes for bulk…

Quantum Physics · Physics 2024-08-28 Saubhik Sarkar , Francesco Ciccarello , Angelo Carollo , Abolfazl Bayat

Parity-time (PT) symmetric non-Hermitian Hamiltonians bring about many novel features and interesting applications such as quantum gates faster than those in Hermitian systems, and topological state transfer. The performance of evolutions…

Quantum Physics · Physics 2022-07-20 Ji Bian , Kunxu Wang , Pengfei Lu , Xinxin Rao , Hao Wu , Qifeng Lao , Teng Liu , Yang Liu , Feng Zhu , Le Luo

We show that similarity (or equivalent) transformations enable one to construct non-Hermitian operators with real spectrum. In this way we can also prove and generalize the results obtained by other authors by means of a gauge-like…

Quantum Physics · Physics 2016-08-08 Francisco M. Fernández

The evolution of entanglement in a non-Hermitian quantum system may behave differently compared to its Hermitian counterpart. In this paper, we investigate the entanglement dynamics of two coupled and driven non-Hermitian qubits. Through…

Quantum Physics · Physics 2023-08-31 Yi-Xi Zhang , Zhen-Tao Zhang , Xiao-Zhi Wei , Bao-Long Liang , Feng Mei , Zhen-Shan Yang

Light propagation in distributed feedback optical structures with gain/loss regions is shown to provide an accessible laboratory tool to visualize in optics the spectral properties of the one-dimensional Dirac equation with non-Hermitian…

Quantum Physics · Physics 2015-05-19 Stefano Longhi

We review the methodology to theoretically treat parity-time- ($\mathcal{PT}$-) symmetric, non-Hermitian quantum many-body systems... (For the full abstract see paper)

Quantum Physics · Physics 2023-11-17 Volker Meden , Lukas Grunwald , Dante M. Kennes

We discuss the basic theoretical framework for non-Hermitian quantum systems with particular emphasis on the diagonalizability of non-Hermitian Hamiltonians and their $GL(1,\mathbb{C})$ gauge freedom, which are relevant to the adiabatic…

Quantum Physics · Physics 2019-04-03 Qi Zhang , Biao Wu

Exceptional points, the spectral degeneracy points in the complex parameter space, are fundamental to non-Hermitian quantum systems. The dynamics of non-Hermitian systems in the presence of exceptional points differ significantly from those…

Quantum Physics · Physics 2021-01-29 Chon-Fai Kam , Yang Chen

Non-Hermitian systems with parity-time symmetry have been developed rapidly and hold great promise for future applications. Unlike most existing works considering the symmetry of the free energy terms (e.g., gain-loss system), in this…

Quantum Physics · Physics 2017-11-21 Wenlin Li , Chong Li , Heshan Song

Two non-Hermitian PT-symmetric Hamiltonian systems are reconsidered by means of the algebraic method which was originally proposed for the pseudo-Hermitian Hamiltonian systems rather than for the PT-symmetric ones. Compared with the way…

Quantum Physics · Physics 2018-01-17 Jun-Qing Li , Qian Li , Yan-Gang Miao

The geometric properties of quantum states is fully encoded by the quantum geometric tensor. The real and imaginary parts of the quantum geometric tensor are the quantum metric and Berry curvature, which characterize the distance and phase…

Quantum Physics · Physics 2024-11-07 Jun-Feng Ren , Jing Li , Hai-Tao Ding , Dan-Wei Zhang

We extensively explore the connections between time-like entanglement and non-hermitian density matrices in quantum many-body systems. We classify setups where we encounter non-hermitian density matrices into two types: one is due to causal…

High Energy Physics - Theory · Physics 2026-02-17 Jonathan Harper , Taishi Kawamoto , Ryota Maeda , Nanami Nakamura , Tadashi Takayanagi

Estimation of physical parameters is a must in almost any part of science and technology. The enhancement of the performances in this task, e.g., beating the standard classical shot-noise limit, using available physical resources is a major…

Quantum Physics · Physics 2014-01-29 F. Benatti , S. Alipour , A. T. Rezakhani

We construct uncertainty relation for arbitrary finite dimensional PT invariant non-Hermitian quantum systems within a special inner product framework. This construction is led by good observables which are a more general class of…

Quantum Physics · Physics 2023-04-11 Namrata Shukla , Ranjan Modak , Bhabani Prasad Mandal

The rationale for introducing non-hermitian Hamiltonians and other observables is reviewed and open issues identified. We present a new approach based on Moyal products to compute the metric for quasi-hermitian systems. This approach is not…

Quantum Physics · Physics 2009-11-13 FG Scholtz , HB Geyer

We discuss systematically several possible inequivalent ways to describe the dynamics and the transition probabilities of a quantum system when its hamiltonian is not self-adjoint. In order to simplify the treatment, we mainly restrict our…

Mathematical Physics · Physics 2015-06-24 Fabio Bagarello

We survey some of the main conceptual developments in the study of PT-symmetric and pseudo-Hermitian Hamiltonian operators that have taken place during the past ten years or so. We offer a precise mathematical description of a quantum…

Quantum Physics · Physics 2015-05-19 Ali Mostafazadeh

Non-Hermitian theory is a theoretical framework that excels at describing open systems. It offers a powerful tool in the characterization of both the intrinsic degrees of freedom (DOFs) of a system and the interactions with the external…

Quantum Physics · Physics 2024-05-28 Kun Ding , Chen Fang , Guancong Ma

We discuss the systematic engineering of quasicrystals in open quantum systems where quasiperiodicity is introduced through purely dissipative processes. While the resulting short-time dynamics is governed by non-Hermitian variants of the…

Quantum Gases · Physics 2022-03-11 Tianyu Li , Yong-Sheng Zhang , Wei Yi

This study investigates pseudo-Hermitian quantum mechanics, where the Hamiltonian satisfies a modified Hermiticity condition. We extend the uncertainty relation for such systems, demonstrating its equivalence to the standard Hermitian case…

Quantum Physics · Physics 2025-08-11 Boubakeur Khantoul , Bilel Hamil , Amar Benchikha