arXiv:0706.4434 · Physical Review A

Pairing of one-dimensional Bose-Fermi mixtures with unequal masses

Matteo Rizzi, Adilet Imambekov

Published Feb 19, 2008• 45 citations

Abstract

We have considered one-dimensional Bose-Fermi mixture with equal densities and unequal masses using numerical density matrix renormalization group. For the mass ratio of K-Rb mixture and attraction between bosons and fermions, we determined the phase diagram. For weak boson-boson interactions, there is a direct transition between two-component Luttinger liquid and collapsed phases as the boson-fermion attraction is increased. For strong enough boson-boson interactions, we find an intermediate ``paired'' phase, which is a single-component Luttinger liquid of composite particles. We investigated correlation functions of such a ``paired'' phase, studied the stability of ``paired'' phase to density imbalance, and discussed various experimental techniques which can be used to detect it.

DOI: 10.1103/physreva.77.023621

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