Local energy density functional for superfluid Fermi gases from effective field theory

Fermionic quantum turbulence: Pushing the limits of high-performance computing

“…Instead, Kohn and Sham ( 5 ) derived an equivalent but alternate formulation in terms of an energy functional of a Slater determinant of single-particle orbitals that allows for an exact local formulation for noninteracting fermions. By including both particles and holes, and with an appropriate regularization procedure, this was generalized for superfluids ( 19–21 , 83 ) in a form called the Slda that we now describe. Unlike the BdG equations, we can now tune the parameters of the theory to match experiment and ab initio Qmc calculations.…”

“…All of these quantities are accessible from Qmc calculations. For more details related to the construction of the functional, see ( 19–23 , 27 , 34 , 83 ) and the source code for the reference implementation. In the calculations presented here, we have assumed that the effective mass , so .…”

Generation and decay of Higgs mode in a strongly interacting Fermi gas

“…The advantage of a description based on DFT is that it allows to incorporate so-called "beyond mean-field" effects, while keeping the numerical complexity at a level comparable to the mean-field methods. Here we use the functional known as SLDAE [33], which has the generic form…”

“…The dimensionless coupling functions A, B and C are constructed in such a way to ensure the correct reproduction of thermodynamics quantities for a uniform system (equation of state, chemical potential, pairing gap, effective mass) over the entire interaction regime from weak (BCS regime) to strong (unitary Fermi gas regime). Their explicit forms are given in paper [33]. The SLDAE functional has been designed to provide accurate results for spin-symmetric systems (N + = N − ), however it can be extended to spin-imbalanced systems as well.…”

Generation and decay of Higgs mode in a strongly interacting Fermi gas

“…The single particle Hamiltonian and the pairing potential are then of the form: The advantage of a description based on DFT is that it allows to incorporate so-called “beyond mean-field” effects, while keeping the numerical complexity at a level comparable to the mean-field methods. Here we use the functional known as SLDAE 49 , which has the generic form where and is the associated Fermi energy. The dimensionless coupling functions A , B and C are constructed in such a way to ensure the correct reproduction of thermodynamics quantities for a uniform system (equation of state, chemical potential, pairing gap, effective mass) over the entire interaction regime from weak (BCS regime) to strong (unitary Fermi gas regime).…”