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A comparative study of a qutrit (three-level atomic system) coupled to a classical field in a typical Markovian reservoir (free space) and in a photonic band-gap (PBG) crystal is carried out. The aim of the study is to assess the collective…

Non-Markovian dynamics go beyond the Markovian approximation by capturing memory effects and information backflow in open quantum systems, which are crucial for describing realistic physical processes. In this work, we study the exact…

Optics · Physics 2025-03-28 H. Z. Shen , Cheng Shang , Yan-Hui Zhou , X. X. Yi

We investigate the qubit in the hierarchical environment where the first level is just one lossy cavity while the second level is the N-coupled lossy cavities. In the weak coupling regime between the qubit and the first level environment,…

Quantum Physics · Physics 2018-08-15 Kai Xu , Wei Han , Ying-Jie Zhang , Yun-Jie Xia , Heng Fan

A rapid restoration of the bath state is usually required to induce Markovian dynamics for an open quantum system, which typically can be realized only in limits such as weak system-bath coupling and infinitely large bath. In this work, we…

Quantum Physics · Physics 2018-01-01 Shengshi Pang , Todd A. Brun , Andrew N. Jordan

We present a new method for evaluating the response of a moving qubit detector interacting with a scalar field in Minkowski spacetime. We treat the detector as an open quantum system, but we do not invoke the Markov approximation. The…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Dimitris Moustos , Charis Anastopoulos

Quantum-speed-limit (QSL) time captures the intrinsic minimal time interval for a quantum system evolving from an initial state to a target state. In single qubit open systems, it was found that the memory (non-Markovian) effect of…

Quantum Physics · Physics 2015-03-18 Chen Liu , Zhen-Yu Xu , Shiqun Zhu

The problem of quantum metrology under the context of a particular non-Markovian quantum evolution is explored. We study the dynamics of the quantum Fisher information (QFI) of a composite quantum probe coupled to a Lorentzian environment,…

Quantum Physics · Physics 2020-09-02 Nicolás Mirkin , Martin Larocca , Diego Wisniacki

The quantum speed limit (QSL) of the Jaynes-Cummings model with detuning for arbitrary initial states is investigated. We mainly focus on the influences of the detuning, width of Lorentzian spectral density, and coherence of the initial…

Quantum Physics · Physics 2023-07-21 Yasin Shahri , Maryam Hadipour , Saeed Haddadi , Hazhir Dolatkhah , Soroush Haseli

The transverse-field XY model in one dimension is a well-known spin model for which the ground state properties and excitation spectrum are known exactly. The model has an interesting phase diagram describing quantum phase transitions…

Quantum Physics · Physics 2015-06-03 Amit Kumar Pal , Indrani Bose

We probe the quantum speed limit (QSL) of an electron when it is trapped in a non-uniform magnetic field. We show that the QSL increases to a large value, but within the regime of causality, by choosing a proper variation in magnetic…

Quantum Physics · Physics 2022-08-26 Srishty Aggarwal , Subhashish Banerjee , Arindam Ghosh , Banibrata Mukhopadhyay

The generic bound of quantum speed limit time (the minimal evolution time) for a qubit system interacting with structural environment is investigated. We define a new bound for the quantum speed limit. It is shown that the non-Markovianity…

Quantum Physics · Physics 2015-09-23 Shao-xiong Wu , Yang Zhang , Chang-shui Yu , He-shan Song

We investigate the influence of an excited-state quantum phase transition (ESQPT) on the quantum speed limit (QSL) time of an open quantum system. The system consists of a central qubit coupled to a spin environment modeled by a…

Quantum Physics · Physics 2019-08-21 Qian Wang , Francisco Perez-Bernal

Quantum information processing requires fast manipulations of quantum systems in order to overcome dissipative effects. We propose a method to accelerate quantum dynamics and obtain a target state in a shorter time relative to unmodified…

Quantum Physics · Physics 2021-09-28 Shumpei Masuda , Jacob Koenig , Gary A. Steele

Characterizing the most efficient evolution, the quantum speed limit (QSL) plays a significant role in quantum technology. How to generalize the well-established QSL from closed systems to open systems has attracted much attention. In…

Quantum Physics · Physics 2023-07-11 Wei Wu , Jun-Hong An

Quantum mechanics is an inherently linear theory. However, collective effects in many body quantum systems can give rise to effectively nonlinear dynamics. In the present work, we analyze whether and to what extent such nonlinear effects…

Quantum Physics · Physics 2022-11-23 Sebastian Deffner

Non-Markovian effects can speed up the dynamics of quantum systems while the limits of the evolution time can be derived by quantifiers of quantum statistical speed. We introduce a witness for characterizing the non-Markovianity of quantum…

In this paper, we study both open-loop control and closed-loop measurement feedback control of non-Markovian quantum dynamics arising from the interaction between a quantum system and its environment. We use the widely studied cavity…

Quantum Physics · Physics 2026-04-14 Haijin Ding , Nina H. Amini , John E. Gough , Guofeng Zhang

Closed quantum systems follow a unitary time evolution that can be simulated on quantum computers. By incorporating non-unitary effects via, e.g., measurements on ancilla qubits, these algorithms can be extended to open-system dynamics,…

Quantum Physics · Physics 2025-05-07 Peter J. Eder , Jernej Rudi Finžgar , Sarah Braun , Christian B. Mendl

Quantum state change can not occurs instantly, but the speed of quantum evolution is limited to an upper bound value, called quantum speed limit (QSL). Engineering QSL is an important task for quantum information and computation science and…

Quantum Physics · Physics 2024-11-11 A. Aaliray , H. Mohammadi

We investigate the dynamics of a two-level system in the presence of an overall environment composed of two layers. The first layer is just one single-mode cavity which decays to memoryless reservoir while the second layer is the two…

Quantum Physics · Physics 2020-06-08 Kai Xu , Guo-Feng Zhang , Wu-Ming Liu