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Non-equilibrium metastable state in a chain of interacting spinless fermions with localized loss

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 نشر من قبل Ameneh Sheikhan
 تاريخ النشر 2019
  مجال البحث فيزياء
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We investigate a chain of spinless fermions with nearest-neighbour interactions that are subject to a local loss process. We determine the time evolution of the system using matrix product state methods. We find that at intermediate times a metastable state is formed, which has very different properties than usual equilibrium states. In particular, in a region around the loss, the filling is reduced, while Friedel oscillations with a period corresponding to the original filling continue to exist. The associated momentum distribution is emptied at all momenta by the loss process and the Fermi edge remains approximately at its original value. Even in the presence of strong interactions, where a redistribution by the scattering is naively expected, such a regime can exist over a long time-scale. Additionally, we point out the existence a system.

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