Quantum speed limit and a signal of quantum criticality

We study the quantum speed limit time (QSLT) of a coupled system consisting of a central spin and its surrounding environment, and the environment is described by a general XY spin-chain model. For initial pure state, we find that the local anomalous enhancement of the QSLT occurs near the critical...

Full description

Bibliographic Details
Main Authors:	Wei, Yong-Bo, Zou, Jian, Wang, Zhao-Ming, Shao, Bin
Format:	Online
Language:	English
Published:	Nature Publishing Group 2016
Online Access:	https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4725993/

id	pubmed-4725993
recordtype	oai_dc
spelling	pubmed-47259932016-01-28 Quantum speed limit and a signal of quantum criticality Wei, Yong-Bo Zou, Jian Wang, Zhao-Ming Shao, Bin Article We study the quantum speed limit time (QSLT) of a coupled system consisting of a central spin and its surrounding environment, and the environment is described by a general XY spin-chain model. For initial pure state, we find that the local anomalous enhancement of the QSLT occurs near the critical point. In addition, we investigate the QSLT for arbitrary time-evolution state in the whole dynamics process and find that the QSLT will decay monotonously and rapidly at a large size of environment near the quantum critical point. These anomalous behaviors in the critical vicinity of XY spin-chain environment can be used to indicate the quantum phase transition point. Especially for the XX spin-chain environment, we find that the QSLT displays a sudden transition from discontinuous segmented values to a steady value at the critical point. In this case, the non-Makovianity and the Loschmidt echo are incapable of signaling the critical value of the transverse field, while the QSLT can still witness the quantum phase transition. So, the QSLT provides a further insight and sharper identification of quantum criticality. Nature Publishing Group 2016-01-19 /pmc/articles/PMC4725993/ /pubmed/26782296 http://dx.doi.org/10.1038/srep19308 Text en Copyright © 2016, Macmillan Publishers Limited http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/
repository_type	Open Access Journal
institution_category	Foreign Institution
institution	US National Center for Biotechnology Information
building	NCBI PubMed
collection	Online Access
language	English
format	Online
author	Wei, Yong-Bo Zou, Jian Wang, Zhao-Ming Shao, Bin
spellingShingle	Wei, Yong-Bo Zou, Jian Wang, Zhao-Ming Shao, Bin Quantum speed limit and a signal of quantum criticality
author_facet	Wei, Yong-Bo Zou, Jian Wang, Zhao-Ming Shao, Bin
author_sort	Wei, Yong-Bo
title	Quantum speed limit and a signal of quantum criticality
title_short	Quantum speed limit and a signal of quantum criticality
title_full	Quantum speed limit and a signal of quantum criticality
title_fullStr	Quantum speed limit and a signal of quantum criticality
title_full_unstemmed	Quantum speed limit and a signal of quantum criticality
title_sort	quantum speed limit and a signal of quantum criticality
description	We study the quantum speed limit time (QSLT) of a coupled system consisting of a central spin and its surrounding environment, and the environment is described by a general XY spin-chain model. For initial pure state, we find that the local anomalous enhancement of the QSLT occurs near the critical point. In addition, we investigate the QSLT for arbitrary time-evolution state in the whole dynamics process and find that the QSLT will decay monotonously and rapidly at a large size of environment near the quantum critical point. These anomalous behaviors in the critical vicinity of XY spin-chain environment can be used to indicate the quantum phase transition point. Especially for the XX spin-chain environment, we find that the QSLT displays a sudden transition from discontinuous segmented values to a steady value at the critical point. In this case, the non-Makovianity and the Loschmidt echo are incapable of signaling the critical value of the transverse field, while the QSLT can still witness the quantum phase transition. So, the QSLT provides a further insight and sharper identification of quantum criticality.
publisher	Nature Publishing Group
publishDate	2016
url	https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4725993/
_version_	1613528023577919488

Quantum speed limit and a signal of quantum criticality

Similar Items