arXiv:1402.1744 · Journal of Statistical Mechanics Theory and Experiment

Evolution of the magnetization after a local quench in the critical transverse-field Ising chain

Ferenc Iglói, Gergő Roósz, Loïc Turban

Published Mar 26, 2014• 14 citations

Abstract

We study the time evolution of the local magnetization in the critical Ising chain in a transverse field after a sudden change of the parameters at a defect. The relaxation of the defect magnetization is algebraic and the corresponding exponent, which is a continuous function of the defect parameters, is calculated exactly. In finite chains the relaxation is oscillating in time and its form is conjectured on the basis of precise numerical calculations.

DOI: 10.1088/1742-5468/2014/03/p03023

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