Surface Effects in the Unitary Fermi Gas

Abstract

We study the extended Thomas-Fermi (ETF) density functional of the superfluid unitary Fermi gas. This functional includes a gradient term which is essential to describe accurately the surface effects of the system, in particular with a small number of atoms, where the Thomas-Fermi (local density) approximation fails. We find that our ETF functional gives density profiles which are in good agreement with recent Monte Carlo results and also with a more sophisticated superfluid density functional based on Bogoliubov-de Gennes equations. In addition, by using extended hydrodynamics equations of superfluids, we calculate the frequencies of collective surface oscillations of the unitary Fermi gas, showing that quadrupole and octupole modes strongly depend on the number of trapped atoms.

18 pages, 5 figures, accepted for publication in Laser Physics Letters

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Cited by in corpus (15)

• Quantized Superfluid Vortex Rings in the Unitary Fermi Gas
• Spontaneous symmetry breaking of Bose-Fermi mixtures in double-well potentials
• Numerical and variational solutions of the dipolar Gross-Pitaevskii equation in reduced dimensions
• Shock waves in strongly interacting Fermi gas from time-dependent density functional calculations
• Validating Simple Dynamical Simulations of the Unitary Fermi Gas
• Low-temperature thermodynamics of the unitary Fermi gas: superfluid fraction, first sound and second sound
• Pair excitations and parameters of state of imbalanced Fermi gases at finite temperatures
• Viscosity-entropy ratio of the unitary Fermi gas from zero-temperature elementary excitations
• Collective modes in the anisotropic unitary Fermi gas and the inclusion of a backflow term
• Dynamical properties of the unitary Fermi gas: collective modes and shock waves
• Stability and collapse of fermions in a binary dipolar boson-fermion 164Dy-161Dy mixture
• Dispersive effects in the unitary Fermi gas
• Unitary Fermi superfluid near the critical temperature: thermodynamics and sound modes from elementary excitations
• Study of a degenerate dipolar Fermi gas of 161Dy atoms
• Three-component Fermi gas with SU(3) symmetry: BCS-BEC crossover in three and two dimensions