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

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 نشر من قبل Loic Turban
 تاريخ النشر 2014
  مجال البحث فيزياء
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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.



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