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arXiv · 1904.08799

Bose polaron in spherical trap potentials: Spatial structure and quantum depletion

Junichi Takahashi·Ryosuke Imai·Eiji Nakano·Kei Iida
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Abstract

We investigate how the presence of a localized impurity in a Bose-Einstein condensate of trapped cold atoms that interact with each other weakly and repulsively affects the profile of the condensed and excited components at zero temperature. By solving the Gross-Pitaevskii and Bogoliubov-de Gennes equations, we find that an impurity-boson contact attraction (repulsion) causes both components to change in spatial structure in such a way as to be enhanced (suppressed) around the impurity, while slightly declining (growing) in a far region from the impurity. Such behavior of the quantum depletion of the condensate can be understood by decomposing the impurity-induced change in the profile of the excited component with respect to the radial and azimuthal quantum number. A significant role of the centrifugal potential and the "hole" excitation level is thus clarified.

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Junichi Takahashi, Ryosuke Imai, Eiji Nakano, Kei Iida. 2019-04-18. Bose polaron in spherical trap potentials: Spatial structure and quantum depletion. https://doi.org/10.1103/physreva.100.023624

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