Persistent currents in Bose–Bose mixtures after an interspecies interaction quench

Abstract

We study the persistent currents and interspecies entanglement generation in a Bose–Bose mixture formed by two atomic gases (hereafter labeled by the letters A and B) trapped in a one-dimensional ring lattice potential with an artificial gauge field after a sudden quench from zero to strong interactions between the two gases. Assuming that the strength of these interactions is much larger than the single species energies and that the gas A is initially in the Mott-insulator regime, we show that the current of the gas B is reduced with respect to its value prior the interaction quench. Averaging fast oscillations out, the relative decrease of this current is independent of the initial visibility and Peierls phase of the gas B and behaves quadratically with the visibility of the gas A. The second Rényi entropy of the reduced state measuring the amount of entanglement between the two gases is found to scale linearly with the number of sites and to be proportional to the relative decrease of the current.

One-BEC-species coherent oscillations with frequency controlled by a second species atom number

“…In particular, extensive research has been carried out in small systems of two wells [40][41][42][43][44][45][46][47][48][49][50][51][52] and three-well rings [36,53]. Very importantly, the tuning of the interaction strength between atoms of distinct species, which is an accessible experimental parameter [54,55], has been suggested as a tool of control of quantum systems [35,[56][57][58][59].…”