Stability of quantum degenerate Fermi gases of tilted polar molecules

Vladimir Veljic; Axel Pelster; Antun Balaz

doi:10.1103/physrevresearch.1.012009

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arXiv · 1902.09518

Stability of quantum degenerate Fermi gases of tilted polar molecules

Vladimir Veljic·Axel Pelster·Antun Balaz

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Abstract

A recent experimental realization of quantum degenerate gas of $^{40}$K$^{87}$Rb molecules opens up prospects of exploring strong dipolar Fermi gases and many-body phenomena arising in that regime. Here we derive a mean-field variational approach based on the Wigner function for the description of ground-state properties of such systems. We show that the stability of dipolar fermions in a general harmonic trap is universal as it only depends on the trap aspect ratios and the dipoles' orientation. We calculate the species-independent stability diagram and the deformation of the Fermi surface (FS) for polarized molecules, whose electric dipoles are oriented along a preferential direction. Compared to atomic magnetic species, the stability of a molecular electric system turns out to strongly depend on its geometry and the FS deformation significantly increases.

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Vladimir Veljic, Axel Pelster, Antun Balaz. 2019-02-25. Stability of quantum degenerate Fermi gases of tilted polar molecules. https://doi.org/10.1103/physrevresearch.1.012009

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