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arXiv · 0812.2231

Supersolid state in fermionic optical lattice systems

Akihisa Koga·Takuji Higashiyama·Kensuke Inaba·Seiichiro Suga·Norio Kawakami
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Abstract

We study ultracold fermionic atoms trapped in an optical lattice with harmonic confinement by combining the real-space dynamical mean-field theory with a two-site impurity solver. By calculating the local particle density and the pair potential in the systems with different clusters, we discuss the stability of a supersolid state, where an s-wave superfluid coexists with a density-wave state of checkerboard pattern. It is clarified that a confining potential plays an essential role in stabilizing the supersolid state. The phase diagrams are obtained for several effective particle densities.

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Akihisa Koga, Takuji Higashiyama, Kensuke Inaba, Seiichiro Suga, Norio Kawakami. 2008-12-11. Supersolid state in fermionic optical lattice systems. https://doi.org/10.1103/physreva.79.013607

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