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arXiv:1905.05029 · Physical Review A

Insulator phases of a mixture of spinor fermions and hard-core bosons

Richard Giovanni Avella, Juan José Mendoza-Arenas, R. Franco, Jereson Silva-Valencia

Published Dec 9, 2019• 8 citations
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Abstract

We study numerically a one-dimensional mixture of spin-$\frac{1}{2}$ fermions and scalar bosons in the hard-core limit. Considering repulsive fermion-fermion and boson-fermion interactions, we find superfluid and insulator states, and determine the boundaries between them calculating several phase diagrams. We determine that, given a fermionic density ${\ensuremath{\rho}}_{F}$, the insulator states are located at the bosonic densities ${\ensuremath{\rho}}_{B}=1\ensuremath{-}{\ensuremath{\rho}}_{F}$ and $1\ensuremath{-}\frac{1}{2}{\ensuremath{\rho}}_{F}$, and emerge even in the absence of fermion-fermion coupling. In addition, the boson-fermion repulsion drives quantum phase transitions inside the insulator lobes with ${\ensuremath{\rho}}_{B}=1/2$. Our predictions could be observed in current cold-atom experimental platforms.

DOI
10.1103/physreva.100.063620

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