Quenching small quantum gases: Genesis of the orthogonality catastrophe

  title={Quenching small quantum gases: Genesis of the orthogonality catastrophe},
  author={Steve Campbell and Miguel 'Angel Garc'ia-March and Thom{\'a}s Fogarty and Thomas Busch},
  journal={Physical Review A},
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… 

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