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arXiv · 0707.4189

Superfluid-Insulator Transition and Fermion Pairing in Bose-Fermi Mixtures

Kun Yang
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Abstract

It is well known that bosons on an optical lattice undergo a second-order superfluid-insulator transition (SIT) when the lattice potential increases. In this paper we study SIT when fermions coexist with the bosons. We find that the critical properties of particle-hole symmetric SIT with dynamical exponent z=1 is modified when fermions are present; it either becomes a fluctuation-driven first order transition or a different second-order transition. On the other hand the more generic particle-hole asymmetric (with z=2) SIT is stable against coupling with fermions. We also discuss pairing interaction between fermions mediated by quantum critical fluctuations near SIT.

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Kun Yang. 2008-02-20. Superfluid-Insulator Transition and Fermion Pairing in Bose-Fermi Mixtures. https://doi.org/10.1103/physrevb.77.085115

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