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Quenching small quantum gases: Genesis of the orthogonality catastrophe

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 نشر من قبل Steve Campbell
 تاريخ النشر 2014
  مجال البحث فيزياء
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We study the dynamics of two strongly interacting bosons with an additional impurity atom trapped in a harmonic potential. Using exact numerical diagonalization we are able to fully explore the dynamical evolution when the interaction between the two distinct species is suddenly switched on (quenched). We examine the behavior of the densities, the entanglement, the Loschmidt echo and the spectral function for a large range of inter-species interactions and find that even in such small systems evidence of Andersons orthogonality catastrophe can be witnessed.



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