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Decoherence of an impurity in a one-dimensional fermionic bath with mass imbalance

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 نشر من قبل Anne-Maria Visuri
 تاريخ النشر 2016
  مجال البحث فيزياء
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We study the transport, decoherence and dissipation of an impurity interacting with a bath of free fermions in a one-dimensional lattice. Numerical simulations are made with the time-evolving block decimation method. We introduce a mass imbalance between the impurity and bath particles and find that the fastest decoherence occurs for a light impurity in a bath of heavy particles. By contrast, the fastest dissipation of energy occurs when the masses are equal. We present a simple model for decoherence in the heavy bath limit, and a linear density response description of the interaction which predicts maximum dissipation for equal masses.


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