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Related papers: Exact zeros of the Loschmidt echo and quantum spee…

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We demonstrate the existence of a dynamical quantum phase transition (DQPT) in a dissipative collective-spin model that exhibits the boundary time crystal (BTC) phase. We initialize the system in the ground state of the Hamiltonian in…

Quantum Physics · Physics 2026-02-05 Sukrut Mondkar , Priya Ghosh , Ujjwal Sen

We study equilibrium as well as dynamical properties of the finite-size fully connected Ising model with a transverse field at the zero temperature. In relation to the equilibrium, we present approximate ground and first excited states that…

Statistical Mechanics · Physics 2021-08-06 Arun Sehrawat , Chirag Srivastava , Ujjwal Sen

In this work it is shown that dynamical quantum phase transitions in Loschmidt echos control the nonequilibrium dynamics of the order parameter after particular quantum quenches in systems with broken-symmetry phases. A direct connection…

Statistical Mechanics · Physics 2014-11-24 Markus Heyl

Interacting many-body systems that are driven far away from equilibrium can exhibit phase transitions between dynamically emerging quantum phases, which manifest as singularities in the Loschmidt echo. Whether and under which conditions…

Statistical Mechanics · Physics 2017-11-08 Simon A. Weidinger , Markus Heyl , Alessandro Silva , Michael Knap

A quantum phase transition is generally thought to imprint distinctive characteristics on the nonequilibrium dynamics of a closed quantum system. Specifically, the Loschmidt echo after a sudden quench to a quantum critical point $-$…

Quantum Physics · Physics 2017-01-09 R. Jafari , Henrik Johannesson

The Loschmidt amplitude of the purified states of mixed-state density matrices is shown to have zeros when the system undergoes a quasistatic, quench, or Uhlmann process. While the Loschmidt-amplitude zero of a quench process corresponds to…

Quantum Physics · Physics 2020-09-24 Xu-Yang Hou , Qu-Cheng Gao , Hao Guo , Yan He , Tong Liu , Chih-Chun Chien

We analyze the dynamics of a Luttinger model following a quench in the electron-electron interaction strength, where the change in the interaction strength occurs over a finite time scale $\tau$. We study the Loschmidt echo (the overlap…

Mesoscale and Nanoscale Physics · Physics 2014-08-27 Rashi Sachdeva , Tanay Nag , Amit Agarwal , Amit Dutta

Dynamical quantum phase transitions are at the forefront of current efforts to understand quantum matter out of equilibrium. Except for a few exactly solvable models, predictions of these critical phenomena typically rely on advanced…

Strongly Correlated Electrons · Physics 2022-07-18 Fredrik Brange , Sebastiano Peotta , Christian Flindt , Teemu Ojanen

We study a Bose-Einstein condensate at the low energy limit and show that their collective dynamics exhibit interesting quantum dynamical behavior. The system undergoes a dynamical quantum phase transition after a sudden quench into a…

Quantum Physics · Physics 2019-11-26 Mehdi Abdi

Dynamical quantum phase transitions (DQPTs) are temporal singularities marked by zeros of the Loschmidt echo, yet their underlying quantum-information structure remains elusive. Here, we introduce a momentum-resolved entanglement entropy as…

Quantum Physics · Physics 2026-01-21 Kaiyuan Cao , Mingzhi Li , Xiang-Ping Jiang , Shu Chen , Jian Wang

We study the Loschmidt echo (LE) in a central spin model in which a central spin is globally coupled to an environment (E) which is subjected to a small and sudden quench at $t=0$ so that its state at $t=0^+$, remains the same as the ground…

Statistical Mechanics · Physics 2012-07-31 Victor Mukherjee , Shraddha Sharma , Amit Dutta

Setting the minimal-time bound for a quantum system to evolve between two distinguishable states, the quantum speed limit (QSL) characterizes the latent capability in speeding up of the system. It has found applications in determining the…

Quantum Physics · Physics 2023-02-02 Wei Wu , Jun-Hong An

By utilizing quantum mechanical effects, such as superposition and entanglement, quantum metrology promises higher precision than the classical strategies. It is, however, practically challenging to realize the quantum advantages. This is…

Quantum Physics · Physics 2025-03-13 Ran Liu , Ze Wu , Xiaodong Yang , Yuchen Li , Hui Zhou , Zhaokai Li , Yuquan Chen , Haidong Yuan , Xinhua Peng

Using local quantum fidelity distances, we study the dynamical quantum phase transition in integrable and non-integrable one-dimensional Ising chains. Unlike the Loschmidt echo, the standard measure for distinguishing between two quantum…

Statistical Mechanics · Physics 2024-08-09 Ruchira V Bhat , Soumya Bera

The recently discovered dynamical phase transition denotes non-analytic behavior in the real time evolution of quantum systems in the thermodynamic limit and has been shown to occur in different systems at zero temperature [Heyl et al.,…

Statistical Mechanics · Physics 2016-03-23 Nils O. Abeling , Stefan Kehrein

The minimum evolution time between multi-qubit quantum states is estimated for non-Markovian quantum channels. We consider the maximally coherent pure and mixed states as well as multi-qubit $X$ states as initial states and discuss the…

Quantum Physics · Physics 2023-01-03 K. G. Paulson , Subhashish Banerjee

We address the time decay of the Loschmidt echo, measuring sensitivity of quantum dynamics to small Hamiltonian perturbations, in one-dimensional integrable systems. Using semiclassical analysis, we show that the Loschmidt echo may exhibit…

Exactly Solvable and Integrable Systems · Physics 2014-02-19 Remy Dubertrand , Arseni Goussev

Quantum speed limit time (QSLT) can be used to characterize the intrinsic minimal time interval for a quantum system evolving from an initial state to a target state. We investigate the QSLT of the open system in Schwarzschild space-time.…

Quantum Physics · Physics 2021-01-20 Kai Xu , Han-Jie Zhu , Guo-Feng Zhang , Jie-Ci Wang , Wu-Ming Liu

Quantum speed limit (QSL) is the lower bound on the time required for a state to evolve to a desired final state under a given Hamiltonian evolution. Three well-known QSLs exist Mandelstam-Tamm (MT), Margolus-Levitin (ML), and dual ML…

Quantum Physics · Physics 2024-10-21 M Suman , S. Aravinda , Ranjan Modak

Quantum speed limit (QSL) is the study of fundamental limits on the evolution time of quantum systems. For instance, under the action of a time-independent Hamiltonian, the evolution time between an initial and a final quantum state obeys…

Quantum Physics · Physics 2024-05-17 H. F. Chau , Wenxin Zeng