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Related papers: The BCS Energy Gap at High Density

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The thermodynamic potential is calculated for a uniform superfluid gas of fermi atoms from the mean field BCS equations including corrections from induced interactions, Hartree-Fock energies and quasiparticle selfenergies. The entropy,…

Superconductivity · Physics 2007-05-23 H. Heiselberg

Assuming a phenomenological self-energy $Im \Sigma(\omega) \sim |\omega|^{\beta\}, (\beta=1 $), which becomes gapped below $T_c$, we derived a new gap equation. The new gap equation contains the effect of the kinetic energy gain upon…

Strongly Correlated Electrons · Physics 2007-05-23 Yunkyu Bang

In the first part of this chapter we analyze the contact intensity $C$, which has been introduced by Tan [Ann. Phys. 323, 2952 (2008)] and appears in several physical observables of the strongly correlated two-component Fermi gas. We…

Quantum Gases · Physics 2012-10-15 Luca Salasnich

We report a model-independent measurement of the entropy, energy, and critical temperature of a degenerate, strongly interacting Fermi gas of atoms. The total energy is determined from the mean square cloud size in the strongly interacting…

Other Condensed Matter · Physics 2009-03-24 L. Luo , B. Clancy , J. Joseph , J. Kinast , J. E. Thomas

We theoretically investigate the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensation (BEC) crossover in a two-dimensional Fermi gas with the finite-range interaction by using the Hartree-Fock-Bogoliubov theory. Expanding the…

Quantum Gases · Physics 2024-03-20 Hikaru Sakakibara , Hiroyuki Tajima , Haozhao Liang

The effective energy of a superconductor $E_{eff}(T)$ at temperature $T$ is defined as the difference between the total energy at temperature $T$ and the total energy at 0~K. We call the energy of the condensate, ${\mathcal E}_c$, the…

Superconductivity · Physics 2016-06-22 Dragos-Victor Anghel , George Alexandru Nemnes

We report the equilibrium vortex phase diagram of a rotating two-band Fermi gas confined to a cylindrically symmetric parabolic trapping potential, using the recently developed finite-temperature effective field theory [Phys. Rev. A…

Quantum Gases · Physics 2018-03-22 S. N. Klimin , J. Tempere , M. V. Milošević

This article is a review o over theory of superconductivity, which is constructed for systems with two overlapping energy bands at the Fermi surface and with arbitrary charge carrier density.There is taken into account all possible kinds of…

Superconductivity · Physics 2007-05-23 M. E. Palistrant

We compute the spectral density in the normal phase of an interacting homogenous Fermi gas using a T-matrix approximation. We fit the quasiparticle peaks of the spectral density to BCS-like dispersion relations, and extract estimates of a…

Quantum Gases · Physics 2015-05-20 Matthew D. Reichl , Erich J. Mueller

We study pseudogap behaviors of ultracold Fermi gases in the BCS-BEC crossover region. We calculate the density of states (DOS), as well as the single-particle spectral weight, above the superfluid transition temperature $T_{\rm c}$…

Quantum Gases · Physics 2015-05-13 S. Tsuchiya , R. Watanabe , Y. Ohashi

We study the evolution of the energy gap in a unitary Fermi gas as a function of temperature. To this end we approximate the Fermi gas by the Hubbard lattice Hamiltonian and solve using the dynamical mean-field approximation. We have found…

Statistical Mechanics · Physics 2009-11-13 Nir Barnea

This article is written as a Lecture given in the 2006 Varenna Summer School on "Ultracold Fermi Gases". Here we present a review of BCS--Bose Einstein condensation (BEC) crossover theory with emphasis on finite temperature effects. We…

Strongly Correlated Electrons · Physics 2011-09-13 K. Levin , Qijin Chen

We have measured the heat capacity of an optically-trapped, strongly-interacting Fermi gas of atoms. A precise input of energy to the gas is followed by single-parameter thermometry, which determines the empirical temperature parameter…

Other Condensed Matter · Physics 2011-09-13 J. Kinast , A. Turlapov , J. E. Thomas , Qijin Chen , Jelena Stajic , K. Levin

Cold atom traps and certain neutron star layers may contain fermions with separation much larger than the range of pair-wise potentials yet much shorter than the scattering length. Such systems can display {\em universal} characteristics…

Strongly Correlated Electrons · Physics 2007-05-23 Zohar Nussinov , Shmuel Nussinov

We investigate the superfluid phase transition in a gas of Fermi atoms loaded on a three-dimensional optical lattice. When the lattice potential is strong, this system can be well described by an attractive Hubbard model. In this model, we…

Materials Science · Physics 2008-03-17 H. Tamaki , Y. Ohashi , K. Miyake

We consider a mass-asymmetric polarized Fermi system in the presence of Hartree-Fock (HF) potentials. We concentrate on the BCS regime with various interaction strengths and numerically obtain the allowed values of the chemical and HF…

Quantum Gases · Physics 2015-06-05 N. Ebrahimian , M. Mehrafarin , R. Afzali

We investigate the non-universal behavior of the BCS-BEC crossover model at the normal to superfluid transition. By using a finite temperature quantum field theoretical approach due to Nozieres and Schmitt-Rink and by making the effective…

Superconductivity · Physics 2007-05-23 L. M. Jensen

We solve numerically various types of the gap equations developed in the relativistic BCS and generalized BCS framework, presented in part I of this paper. We apply the method for, not only the usual solid metal but also other physical…

Superconductivity · Physics 2008-12-18 Tadafumi Ohsaku

A detailed analysis is given of the effects of common and recurring approximations used in conventional superconductivity theories on the condensation energy values, whose magnitudes are notoriously smaller than those of other energies as…

Superconductivity · Physics 2022-10-19 I. Chávez , P. Salas , M. A. Solís , M. de Llano

The confinement of a superconductor in a thin film changes its Fermi-level density of states and is expected to change its critical temperature $T_c$. Previous calculations have reported large discontinuities of $T_c$ when the chemical…

Superconductivity · Physics 2016-08-26 D. Valentinis , D. van der Marel , C. Berthod