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

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In this paper, we systematically study the work statistics for quantum phase transition. For a quantum system approached by an anisotropic conformal field theory near the critical point, the driving protocols is divided into three different…

Statistical Mechanics · Physics 2021-05-05 Zhaoyu Fei , C. P. Sun

Quantum speed limit (QSL) is a fundamental concept in quantum mechanics and provides a lower bound on the evolution time. The attainability of QSL, greatly depending on the understanding of QSL, is a long-standing open problem especially…

Quantum Physics · Physics 2025-11-07 Zi-yi Mai , Chang-shui Yu

We investigate the out-of-equilibrium dynamics after a quantum quench of the reduced fidelities between the states of a subregion $A$ at different times. Precisely, we consider the fidelity between the time-dependent state of $A$ and its…

Statistical Mechanics · Physics 2026-01-27 Gilles Parez , Vincenzo Alba

We consider the dynamics of maximal quantum Fisher information (MQFI) after sudden quenches for the one-dimensional transverse-field Ising model. Our results show, the same as Loschmidt echo, there is a universality for the revival times…

Quantum Physics · Physics 2020-11-17 Hadi Cheraghi , Saeed Mahdavifar

We study the slow quenching dynamics (characterized by an inverse rate, $\tau^{-1}$) of a one-dimensional transverse Ising chain with nearest neighbor ferromagentic interactions across the quantum critical point (QCP) and analyze the…

Statistical Mechanics · Physics 2016-06-08 Shraddha Sharma , Uma Divakaran , Anatoli Polkovnikov , Amit Dutta

We uncover a novel dynamical quantum phase transition, using random matrix theory and its associated notion of planar limit. We study it for the isotropic XY Heisenberg spin chain. For this, we probe its real-time dynamics through the…

Quantum Physics · Physics 2024-03-04 David Pérez-García , Leonardo Santilli , Miguel Tierz

Limitations to the speed of evolution of quantum systems, typically referred to as quantum speed limits (QSLs), have important consequences for quantum control problems. However, in its standard formulation, is not straightforward to obtain…

Quantum Physics · Physics 2022-01-06 Pablo M. Poggi

We study the quench dynamics on cross-stitch flat band networks by a sudden change of the inter-cell hopping strength $J$. For quench processes with $J$ changing as $J=0\rightarrow J\neq0$, we give the analytical expression to the Loschmidt…

Quantum Gases · Physics 2019-04-03 Tong Liu , Hao Guo

We consider the computation of the Loschmidt echo after quantum quenches in the interacting $XXZ$ Heisenberg spin chain both for real and imaginary times. We study two-site product initial states, focusing in particular on the N\'eel and…

Statistical Mechanics · Physics 2017-02-17 Lorenzo Piroli , Balázs Pozsgay , Eric Vernier

We discuss a class of quantum speed limits (QSLs) based on unified quantum ($\alpha,\mu$)-entropy for nonunitary physical processes. The bounds depend on both the Schatten speed and the smallest eigenvalue of the evolved state, and the…

Quantum Physics · Physics 2022-07-06 Diego Paiva Pires

We formulate dynamical phase transitions in subsystems embedded in larger quantum systems. Introducing the entanglement echo as an overlap of the initial and instantaneous entanglement ground states, we show its analytic structure after a…

Quantum Physics · Physics 2021-06-21 Kim Pöyhönen , Teemu Ojanen

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…

Quantum Physics · Physics 2026-01-01 Dong-Ping Xuan , Zhi-Xi Wang , Shao-Ming Fei

Quantum sensors capitalize on advanced control sequences for maximizing sensitivity and precision. However, protocols are not usually optimized for temporal resolution. Here, we establish the limits for time-resolved sensing of dynamical…

Quantum Physics · Physics 2024-12-12 Konstantin Herb , Christian L. Degen

The traditional quantum speed limits are not attainable for many physical processes, as they tend to be loose and fail to determine the exact time taken by quantum systems to evolve. To address this, we derive exact quantum speed limits for…

Quantum Physics · Physics 2023-08-30 Arun K. Pati , Brij Mohan , Sahil , Samuel L. Braunstein

Dynamical phase transition in quantum many body systems is usually studied by taking it in the ground state and then quenching a parameter to a new value. We investigate here the dynamics when one performs the time evolution of a generic…

Statistical Mechanics · Physics 2020-08-04 Sirshendu Bhattacharyya , Subinay Dasgupta

The behavior of quantum speed limit time (QSLT) for a single free spin $-1/2$ particle described by Gaussian wavepackets in the framework of relativity under dephasing noise is investigated. The dephasing noise acts only on the spin degrees…

Quantum Physics · Physics 2016-12-22 Salman Khan , Niaz Ali Khan

Quantum mechanics imposes a lower bound on the time required for a quantum system to reach certain given targets. In this paper, from a geometric perspective, we introduce a new quantum speed limit (QSL) based on the Bloch angle and derive…

Quantum Physics · Physics 2025-07-02 Qianyi Wang , Ben Wang , Jun Wang , Lijian Zhang

The notion of a dynamical quantum phase transition (DQPT) was recently introduced in [Heyl et al., Phys. Rev. Lett. 110, 135704 (2013)] as the non-analytic behavior of the Loschmidt echo at critical times in the thermodynamic limit. In this…

Statistical Mechanics · Physics 2015-09-04 Markus Schmitt , Stefan Kehrein

We derive a new quantum speed limit (QSL) for open quantum systems governed by Markovian dynamics. By analyzing the time derivative of the Bures angle between the initial pure state and its time-evolved state, we obtain an analytically…

Quantum Physics · Physics 2025-07-04 Kohei Kobayashi

We study the ground state fidelity, fidelity susceptibility and quench dynamics of the extended quantum compass model in a transverse field. This model reveals a rich phase diagram which includes several critical surfaces depending on…

Statistical Mechanics · Physics 2016-04-04 R. Jafari