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Related papers: On the BCS gap equation for superfluid fermionic g…

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The equation for the gap parameter represents the main equation of the pairing theory of superconductivity. Although it is formally defined through a single-particle property, physically it reflects the pairing correlations between…

Superconductivity · Physics 2018-09-19 L. Pisani , P. Pieri , G. Calvanese Strinati

We consider a very asymmetric system of Fermions with an interaction characterized by a positive scattering length only. The minority atoms pair and form a BEC of dimers, while the surplus fermions interact only indirectly through the…

Statistical Mechanics · Physics 2009-05-15 Aurel Bulgac , Sukjin Yoon

We study the zero temperature non-equilibrium dynamics of a fermionic superfluid in the BCS limit and in the presence of a drive leading to a time dependent chemical potential $\mu(t)$. We choose a periodic driving protocol characterized by…

Quantum Gases · Physics 2013-10-29 Analabha Roy , Raka Dasgupta , Sanhita Modak , Arnab Das , K. Sengupta

We discuss the superfluid phase transition of a strongly interacting Fermi gas with unequal (asymmetric) chemical potentials in two pairing hyperfine states, and map out its phase diagram near the BCS-BEC crossover. Our approach includes…

Statistical Mechanics · Physics 2007-05-23 Xia-Ji Liu , Hui Hu

We study analytic solutions to the Bardeen-Cooper-Schrieffer (BCS) gap equation for isotropic superconductors with finite-range interaction potentials over the full range of temperatures from absolute zero to the superconducting critical…

Superconductivity · Physics 2023-09-21 Edwin Langmann , Christopher Triola

This is an introductory lecture to the theory of degenerate Fermi gases, in the context of present experiments on atomic Fermi gases. In part one, some properties of the ideal Fermi gas are presented, including a discussion of the…

Other Condensed Matter · Physics 2009-03-02 Yvan Castin

We investigate the transport properties of a superfluid Fermi gas confined in a ring trap with a moving potential barrier across the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensate (BEC) crossover. Employing time-dependent…

Quantum Gases · Physics 2026-05-19 Hikaru Kuriki , Masaya Kunimi , Tetsuro Nikuni

We extend a recently introduced separable interaction for the unitary trapped Fermi gas to all values of the scattering length. We derive closed expressions for the interaction matrix elements and the two-particle eigenvectors and…

Quantum Gases · Physics 2012-06-27 C. N. Gilbreth , Y. Alhassid

Motivated by recent experimental advances in ultracold atoms, we analyze a non-Hermitian (NH) BCS Hamiltonian with a complex-valued interaction arising from inelastic scattering between fermions. We develop a mean-field theory to obtain a…

Pairing is the fundamental requirement for fermionic superfluidity and superconductivity. To understand the mechanism behind pair formation is an ongoing challenge in the study of many strongly correlated fermionic systems. Cooper pairs are…

We derive the phase diagram for ultracold trapped dipolar Fermi gases. Below the critical value of the dipole-dipole interaction energy, the BCS transition into a superfluid phase ceases to exist. The critical dipole strength is obtained as…

Condensed Matter · Physics 2009-11-10 M. A. Baranov , L. Dobrek , M. Lewenstein

Most theoretical treatments of inhomogeneous superconductivity/fermionic superfluidity have been based on the Bogoliubov-deGennes equations (or, else, on their various simplified forms), which implement a standard mean-field decoupling in…

Superconductivity · Physics 2024-03-25 Leonardo Pisani , Verdiana Piselli , Giancarlo Calvanese Strinati

We analyze the BCS-BEC crossover for a Fermi gas made of neutral atoms in three hyperfine states with a SU(3) invariant attractive interaction. By solving the extended BCS equations for the total number of particles and the pairing gap, we…

Quantum Gases · Physics 2012-11-27 Luca Salasnich

We consider pairing in a dilute system of Fermions with a short-range interaction. While the theory is ill-defined for a contact interaction, the BCS equations can be solved in the leading order of low-energy effective field theory. The…

Nuclear Theory · Physics 2011-07-18 Thomas Papenbrock , George F. Bertsch

We investigate the dynamical properties of a superfluid gas of trapped fermionic atoms in the BCS phase. As a simple example we consider the reaction of the gas to a slow rotation of the trap. It is shown that the currents generated by the…

Other Condensed Matter · Physics 2009-11-10 Michael Urban

We propose a Bragg spectroscopy experiment to measure the onset of superfluid pairing in ultracold trapped Fermi gases. In particular, we study two component Fermi gases in the weak coupling BCS and BEC limits as well as in the strong…

Superconductivity · Physics 2007-05-23 G. M. Bruun , Gordon Baym

We review the BCS to Bose Einstein condensation (BEC) crossover scenario which is based on the well known crossover generalization of the BCS ground state wavefunction $\Psi_0$. While this ground state has been summarized extensively in the…

Superconductivity · Physics 2011-09-13 Qijin Chen , Jelena Stajic , Shina Tan , Kathryn Levin

In a trapped atomic Fermi gas, one can tune continuously via a Feshbach resonance the effective pairing interaction between fermionic atoms from very weak to very strong. As a consequence, the low temperature superfluidity evolves…

Quantum Gases · Physics 2011-01-17 Yi Yu , Qijin Chen

We calculate the normal mass density of a paired Fermi gas at unitarity. The dominant contribution near the superfluid transition is from fermionic quasiparticle excitations, and is thus sensitive to the pairing gap. A comparison with the…

Quantum Gases · Physics 2013-10-25 Gordon Baym , C. J. Pethick

Monte Carlo simulations of the 3+1 dimensional NJL model are performed with baryon chemical potential mu>0. For mu>Sigma_0, the constituent quark mass in vacuum, chiral symmetry is restored and a diquark condensate <qq_+> forms. We analyse…

High Energy Physics - Lattice · Physics 2009-11-10 David N. Walters , Simon Hands