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Title: Time Dependence of Correlation Functions Following a Quantum Quench

Abstract

We show that the time dependence of correlation functions in an extended quantum system in d dimensions, which is prepared in the ground state of some Hamiltonian and then evolves without dissipation according to some other Hamiltonian, may be extracted using methods of boundary critical phenomena in d+1 dimensions. For d=1 particularly powerful results are available using conformal field theory. These are checked against those available from solvable models. They may be explained in terms of a picture, valid more generally, whereby quasiparticles, entangled over regions of the order of the correlation length in the initial state, then propagate classically through the system.

Authors:
 [1];  [2]
  1. Institute for Theoretical Physics, University of Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam (Netherlands)
  2. Oxford University, Rudolf Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford, OX1 3NP, United Kingdom and All Souls College, Oxford (United Kingdom)
Publication Date:
OSTI Identifier:
20775157
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 13; Other Information: DOI: 10.1103/PhysRevLett.96.136801; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 36 MATERIALS SCIENCE; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CONFORMAL INVARIANCE; CORRELATION FUNCTIONS; GROUND STATES; HALL EFFECT; HAMILTONIANS; QUANTUM FIELD THEORY; QUASI PARTICLES; TIME DEPENDENCE

Citation Formats

Calabrese, Pasquale, and Cardy, John. Time Dependence of Correlation Functions Following a Quantum Quench. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.136801.
Calabrese, Pasquale, & Cardy, John. Time Dependence of Correlation Functions Following a Quantum Quench. United States. doi:10.1103/PhysRevLett.96.136801.
Calabrese, Pasquale, and Cardy, John. Fri . "Time Dependence of Correlation Functions Following a Quantum Quench". United States. doi:10.1103/PhysRevLett.96.136801.
@article{osti_20775157,
title = {Time Dependence of Correlation Functions Following a Quantum Quench},
author = {Calabrese, Pasquale and Cardy, John},
abstractNote = {We show that the time dependence of correlation functions in an extended quantum system in d dimensions, which is prepared in the ground state of some Hamiltonian and then evolves without dissipation according to some other Hamiltonian, may be extracted using methods of boundary critical phenomena in d+1 dimensions. For d=1 particularly powerful results are available using conformal field theory. These are checked against those available from solvable models. They may be explained in terms of a picture, valid more generally, whereby quasiparticles, entangled over regions of the order of the correlation length in the initial state, then propagate classically through the system.},
doi = {10.1103/PhysRevLett.96.136801},
journal = {Physical Review Letters},
number = 13,
volume = 96,
place = {United States},
year = {Fri Apr 07 00:00:00 EDT 2006},
month = {Fri Apr 07 00:00:00 EDT 2006}
}
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