Michael FLEISCHHAUER
The talk will discuss the interaction of heavy point-like quantum impurities with a one-dimensional quasi condensate in the strong coupling limit in equilibrium and under non-equilibrium conditions as well as in the presence of noise. I will start by summarizing our results on the ground state of a single impuritiy [1] and the mediated interaction of a pair of them [2]. They were obtained by a semi-analytical approach of linearized quantum fluctuations on a deformed condensate and benchmarked by Quantum Monte Carlo simulations. I will then discuss the dynamics of impurities injected into the condensate under adiabatic and non-adiabatic conditions. Finally I will consider the interaction of noisy impurities with a condensate. Point-like impurities with a fluctuating, Markovian coupling to the BEC can lead to rich dynamics of induced superfluid flow and incoherent counterflows in the condensate.
[1] J. Jager, R. Barnett, M. Will, and M. Fleischhauer; Phys. Rev. Res. 2, 033142 (2020)[2] M. Will, G. E. Astrakarchik, and M. Fleischhauer; Phys. Rev. Lett. 127, 103401 (2021)