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arXiv · 0706.4434

Pairing of 1D Bose-Fermi mixtures with unequal masses

M. Rizzi·A. Imambekov
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Abstract

We have considered one-dimensional Bose-Fermi mixture with equal densities and unequal masses using numerical density matrix renormalization group (DMRG). 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.

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M. Rizzi, A. Imambekov. 2008-03-12. Pairing of 1D Bose-Fermi mixtures with unequal masses. https://doi.org/10.1103/physreva.77.023621

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