Nonequilibrium quantum relaxation across a localization-delocalization transition

Gergo Roósz, Uma Divakaran, Heiko Rieger, F. Iglói

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

We consider the one-dimensional XX model in a quasiperiodic transverse field described by the Harper potential, which is equivalent to a tight-binding model of spinless fermions with a quasiperiodic chemical potential. For weak transverse field (chemical potential), hhc. We study the nonequilibrium relaxation of the system by applying two protocols: a sudden change of h (quench dynamics) and a slow change of h in time (adiabatic dynamics). For a quench into the delocalized (localized) phase, the entanglement entropy grows linearly (saturates) and the order parameter decreases exponentially (has a finite limiting value). For a critical quench the entropy increases algebraically with time, whereas the order parameter decreases with a stretched exponential. The density of defects after an adiabatic field change through the critical point is shown to scale with a power of the rate of field change and a scaling relation for the exponent is derived.

Original languageEnglish
Article number184202
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume90
Issue number18
DOIs
Publication statusPublished - Nov 7 2014

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Chemical potential
Entropy
Fermions
entropy
Defects
critical point
fermions
exponents
scaling
defects

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

Nonequilibrium quantum relaxation across a localization-delocalization transition. / Roósz, Gergo; Divakaran, Uma; Rieger, Heiko; Iglói, F.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 90, No. 18, 184202, 07.11.2014.

Research output: Contribution to journalArticle

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