Unconventional quantum phases of lattice bosonic mixtures

Abstract

We consider strongly interacting boson-boson mixtures on one-dimensional lattices and, by adopting a qualitative mean-field approach, investigate their quantum phases as the interspecies repulsion is increased. In particular, we analyze the low-energy "quantum emulsion" metastable states occurring at large values of the interspecies interaction, which are expected to prevent the system from reaching its true ground state. We argue a significant decrease in the visibility of the time-of-flight images in the case of these spontaneously disordered states.

10 pages, 2 figures - to appear in the topical issue on "Novel Quantum Phases and Mesoscopic Physics in Quantum Gases" of the European Physical Journal B (2009)