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arXiv · 1301.5133

Critical velocity, vortex shedding and drag in a unitary Fermi superfluid

F. Ancilotto·L. Salasnich·F. Toigo
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Abstract

We study the real-time motion of a microscopic object in a cold Fermi gas at unitary conditions by using an extended Thomas-Fermi density functional approach. We find that spontaneous creation of singly quantized vortex-antivortex pairs occurs as a critical velocity is exceeded, which leads to a drag between the moving object and the Fermi gas. The resulting force is linear in the velocity for subsonic motion and becomes quadratic for supersonic motion.

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F. Ancilotto, L. Salasnich, F. Toigo. 2013-01-22. Critical velocity, vortex shedding and drag in a unitary Fermi superfluid. https://doi.org/10.1103/physreva.87.013637

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