2013/08/31 by Steffen Patrick Rath, Richard Schmidt · 1 citation
Physics and Astronomy · #cond-mat.quant-gas #quant-ph
paper · pdf · doi:10.1103/physreva.88.053632
published as Phys. Rev. A 88, 053632 (2013) · 11+7 pages, 10 figures. Published Version. Title changed accordingly
arxiv created 2013/12/16 · arxiv updated 2013/12/17
We study the properties of the Bose polaron, an impurity strongly interacting with a Bose-Einstein condensate, using a field-theoretic approach and make predictions for the spectral function and various quasiparticle properties that can be tested in experiment. We find that most of the spectral weight is contained in a coherent attractive and a metastable repulsive polaron branch. We show that the qualitative behavior of the Bose polaron is well described by a non-selfconsistent T-matrix approximation by comparing analytical results to numerical data obtained from a fully selfconsistent T-matrix approach. The latter takes into account an infinite number of bosons excited from the condensate.