arXiv:1207.3449 · Physical Review A

Persistent currents in a bosonic mixture in the ring geometry

Konstantin Anoshkin, Zhigang Wu, E. Zaremba

Published Jul 8, 2013• 35 citations

Abstract

In this paper we analyze the possibility of persistent currents of a two-species bosonic mixture in the one-dimensional ring geometry. We extend the arguments used by F. Bloch [Phys. Rev. A 7, 2187 (1973)] to obtain a criterion for the stability of persistent currents for the two-species system. If the mass ratio of the two species is a rational number, persistent currents can be stable at multiples of a certain total angular momenta. We show that the Bloch criterion can also be viewed as a Landau criterion involving the elementary excitations of the system. Our analysis reveals that persistent currents at higher angular momenta are more stable for the two-species system than previously thought.

DOI: 10.1103/physreva.88.013609

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