Correlation effects in the quench-induced phase separation dynamics of a two species ultracold quantum gas

Abstract

We explore the quench dynamics of a binary Bose-Einstein condensate crossing the miscibilityimmiscibility threshold and vice versa, both within and in particular beyond the mean-field approximation. Increasing the interspecies repulsion leads to the filamentation of the density of each species, involving shorter wavenumbers and longer spatial scales in the many-body approach. These filaments appear to be strongly correlated and exhibit domain-wall structures. Following the reverse quench process multiple dark-antidark solitary waves are spontaneously generated and subsequently found to decay in the many-body scenario. We simulate single-shot images to connect our findings to possible experimental realizations. Finally, the growth rate of the variance of a sample of single-shots probes the degree of entanglement inherent in the system.

Many-body quantum dynamics and induced correlations of Bose polarons

“…Note also that the inclusion of the Thomas-Fermi approximation in the effective potential of equation (15) can not adequately describe the impurities dynamics when they reach the edges of the bosonic cloud, see [36] for more details. However in this case ( ) [35,65]. Furthermore, for these weak postquench interspecies repulsions a similar to the above-described dynamics takes place also for two weakly (g II =0.2) repulsively interacting impurities as shown in figure 5(c).…”

“…To calculate the stationary properties and to track the MB non-equilibrium quantum dynamics of the multicomponent bosonic system discussed above we employ the ML-MCTDHX method [70][71][72]. This is an ab initio variational method for solving the time-dependent MB Schrödinger equation of atomic mixtures and it is based on the expansion of the total MB wavefunction with respect to a time-dependent and variationally optimized basis tailored to capture both the intra-and the interspecies correlations of a multicomponent system [35,65,81,82].…”

“…, where the miscibility/immiscibility transition between the impurity and the BEC takes place [65,67], the behavior of á ñ  r is suddenly altered. Indeed for , where the two impurities residing either on the left or the right edge of the Thomas-Fermi profile of the BEC.…”

Repulsive Fermi polarons and their induced interactions in binary mixtures of ultracold atoms

“…where A ij (t) denote the time-dependent expansion coefficients. Equation (2) is equivalent to a truncated Schmidt decomposition of rank M [71,81,82]. Indeed, the spectral decomposition of the expansion coefficients A ij reads…”

“…In this way the general ansatz of equation (2) becomes that of equation (8) (see also the discussion in section 4). For a detailed discussion on this ansatz we refer the reader to [80][81][82].…”