Extended Thomas-Fermi density functional for the unitary Fermi gas

Thomas–Fermi Approximation and Basics of the Density Functional Theory

As stated at the beginning of section 2.7 the total energy is a key function describing the basic physical and chemical properties of materials: the ground state. It consists of both kinetic (describing motion) and potential energy parts. To make a theoretical model realistic it is very important to incorporate all important contributions to both the parts of the total energy. In view of the bi...

Unitary Fermi gas in the ǫ expansion

We construct systematic expansions around four and two spatial dimensions for a Fermi gas near the unitarity limit. Near four spatial dimensions such a Fermi gas can be understood as a weaklyinteracting system of fermionic and bosonic degrees of freedom. To the leading and next-to-leading orders in the expansion over ǫ = 4 − d, with d being the dimensionality of space, we calculate the thermody...

Damping of a unitary Fermi gas.

We measure the temperature dependence of the radial breathing mode in an optically trapped, unitary Fermi gas of 6Li, just above the center of a broad Feshbach resonance. The damping rate reveals a clear change in behavior which we interpret as arising from a superfluid transition. We suggest pair breaking as a mechanism for an increase in the damping rate which occurs at temperatures well abov...

Dipole Moments in Thomas-Fermi-Dirac and Thomas-Fermi Theories

Measurement of universal thermodynamic functions for a unitary Fermi gas.

Thermodynamic properties of matter generally depend on the details of interactions between its constituent parts. However, in a unitary Fermi gas where the scattering length diverges, thermodynamics is determined through universal functions that depend only on the particle density and temperature. By using only the general form of the equation of state and the equation of force balance, we meas...