Physica Scripta

Interplay of localization lengths in two-component mixtures of one-dimensional cold atoms

François Crépin, Gergely Zaránd, Pascal Simon

Published Nov 1, 2012• 0 citations

Abstract

The interplay between disorder and interactions in quantum systems is a long-standing topic of condensed matter physics. We study the fate of a two-component one-dimensional mixture of cold atoms in the presence of a weak random potential. We show how disorder-induced localization of one species can influence the localization of the other species through interactions and identity three distinct phases: a delocalized phase described by a two-component Luttinger liquid, a hybrid phase where only one species is localized and a fully localized phase where both components of the mixture are localized. The latter phase is characterized by two nested localization length scales. We present the possible signatures of these phases in various observables such as the structure factors (related to Bragg scattering experiments) and the momentum distributions observed in time-of-flight experiments.

DOI: 10.1088/0031-8949/2012/t151/014058

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