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Fluctuations and stochastic processes in one-dimensional many-body quantum systems

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 نشر من قبل Igor E. Mazets
 تاريخ النشر 2009
  مجال البحث فيزياء
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We study the fluctuation properties of a one-dimensional many-body quantum system composed of interacting bosons, and investigate the regimes where quantum noise or, respectively, thermal excitations are dominant. For the latter we develop a semiclassical description of the fluctuation properties based on the Ornstein-Uhlenbeck stochastic process. As an illustration, we analyze the phase correlation functions and the full statistical distributions of the interference between two one-dimensional systems, either independent or tunnel-coupled and compare with the Luttinger-liquid theory.

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