2020/03/31 by Moritz Drescher, Manfred Salmhofer, Tilman Enss · 1 citation
Physics and Astronomy · #cond-mat.quant-gas #cond-mat.str-el #quant-ph
paper · pdf · doi:10.1103/physrevresearch.2.032011
published as Phys. Rev. Research 2, 032011(R) (2020) · 6 pages, 3 figures; published version
arxiv created 2020/07/13 · arxiv updated 2021/02/02
We investigate a Bose-Einstein condensate in strong interaction with a single impurity particle. While this situation has received considerable interest in recent years, the regime of strong coupling remained inaccessible to most approaches due to an instability in Bogoliubov theory arising near the resonance. We present a nonlocal extension of Gross-Pitaevskii theory that is free of such divergences and does not require the use of the Born approximation in any of the interaction potentials. We find a new dynamical transition regime between attractive and repulsive polarons, where an interaction quench results in a finite number of coherent oscillations in the density profiles of the medium and in the contact parameter before equilibrium is reached.