Dynamical effects of exchange symmetry breaking in mixtures of interacting bosons

摘要

In a double-well potential, a Bose-Einstein condensate exhibits Josephson oscillations or self-trapping,ndepending on its initial preparation and on the ratio of interparticle interaction to interwell tunneling. Here, wenelucidate the role of the exchange symmetry for the dynamics with a mixture of two distinguishable species withnidentical physical properties, that is, which are governed by an isospecific interaction and external potential. Innthe mean-field limit, the spatial population imbalance of the mixture can be described by the dynamics of a singlenspecies in an effective potential with modified properties or, equivalently, with an effective total particle number.nThe oscillation behavior can be tuned by populating the second species while maintaining the spatial populationnimbalance and all other parameters constant. In the corresponding many-body approach, the single-speciesndescription approximates the full counting statistics well also outside the realm of spin-coherent states. Thenmethod is extended to general Bose-Hubbard systems and to their classical mean-field limits, which suggests anneffective single-species description of multicomponent Bose gases with weakly an-isospecific interactions.