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arXiv · 1206.3904

Liquid and crystal phase of dipolar fermions in two dimensions

Abstract

The liquid and crystal phase of a single-component Fermi gas with dipolar interactions are investigated using quantum Monte Carlo methods in two spatial dimensions and at zero temperature. The dipoles are oriented by an external field perpendicular to the plane of motion, resulting in a purely repulsive 1/r^3 interaction. In the liquid phase we calculate the equation of state as a function of the interaction strength and other relevant properties characterizing the Fermi-liquid behavior: effective mass, discontinuity at the Fermi surface and pair correlation function. In the high density regime we calculate the equation of state of the Wigner crystal phase and the critical density of the liquid to solid first order phase transition. Close to the freezing density we also search for the existence of a stripe phase, but such a phase is never found to be energetically favorable.

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BibTeXRIS

N. Matveeva, S. Giorgini. 2012-06-18. Liquid and crystal phase of dipolar fermions in two dimensions. https://doi.org/10.1103/physrevlett.109.200401

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