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Related papers: BCS-BEC crossover in relativistic Fermi systems

200 papers

The realization of BCS-BEC crossover in superconductors, which smoothly connects Bardeen-Cooper-Schrieffer (BCS) theory with Bose-Einstein Condensation (BEC) in fermion systems, is an intriguing recent topic in strongly correlated electron…

Superconductivity · Physics 2025-02-20 Hiroshi Watanabe , Hiroaki Ikeda

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

The superfluidity and pairing phenomena in ultracold atomic Fermi gases have been of great interest in recent years, with multiple tunable parameters. Here we study the BCS-BEC crossover behavior of balanced two-component Fermi gases in a…

Quantum Gases · Physics 2020-05-20 Jibiao Wang , Leifeng Zhang , Yi Yu , Chaohong Lee , Qijin Chen

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 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 study ultracold superfluid Bose-Fermi mixtures in three dimensions, with stronger confinement along one or two directions, using a non-perturbative beyond-mean-field model for bulk chemical potential valid along the weak-coupling to…

Quantum Gases · Physics 2023-08-29 Pardeep Kaur , Sandeep Gautam , S. K. Adhikari

We analyze the phase diagram of superfluidity for two-species fermion mixtures from the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensation (BEC) limit as a function of scattering parameter, population imbalance and mass…

Superconductivity · Physics 2009-11-13 M. Iskin , C. A. R. Sa de Melo

We study the persistent currents of an attractive Fermi gas confined in a tightly-confining ring trap and subjected to an artificial gauge field all through the BCS-BEC crossover. At weak attractions, on the BCS side, fermions display a…

Quantum Gases · Physics 2021-09-22 Giovanni Pecci , Piero Naldesi , Luigi Amico , Anna Minguzzi

We have demonstrated that it is possible to access a crossover scenario starting with a weak coupling (BCS) d-wave superconductor to a strongly coupled Bose-Einstein condensate (BEC) phase as the exchange interaction is tuned in a two…

Strongly Correlated Electrons · Physics 2015-06-15 Subrat Kumar Das , Ayan Khan , Saurabh Basu

We show how to describe the $T \neq 0$ behavior associated with the usual BCS- Bose Einstein condensation (BEC) crossover ground state. We confine our attention here to the BEC and near-BEC regime where analytical calculations are possible.…

Soft Condensed Matter · Physics 2011-09-13 Jelena Stajic , Qijin Chen , K. Levin

This paper gives a survey of a diagrammatic approach for fermionic pairing fluctuations, which are relevant to the BCS-BEC crossover realized with ultracold Fermi gases. Emphasis will be given to the physical intuition about the relevant…

Quantum Gases · Physics 2010-11-29 G. C. Strinati

Strong evidence for pairing and superfluidity has recently been found in atomic Fermi gases at the BCS-BEC crossover both in collective modes and RF excitation energies. It is argued that the scale for the effective pairing gaps measured in…

Superconductivity · Physics 2009-11-10 H. Heiselberg

We study a gas of fermions undergoing a wide resonance s-wave BCS-BEC crossover, in the BEC regime at zero temperature. We calculate the chemical potential and the speed of sound of this Bose-condensed gas, as well as the condensate…

Superconductivity · Physics 2009-11-11 J. Levinsen , V. Gurarie

We study the effects of an external periodic potential on the critical velocity of a superfluid Fermi gas in the crossover between the Bardeen-Cooper-Schrieffer (BCS) phase and Bose-Einstein condensation (BEC). We numerically solve the…

Quantum Gases · Physics 2011-08-04 Gentaro Watanabe , Franco Dalfovo , Lev P. Pitaevskii , Sandro Stringari

We calculate the parameters of the Ginzburg-Landau (GL) equation of a three-dimensional attractive Fermi gas around the superfluid critical temperature. We compare different levels of approximation throughout the Bardeen-Cooper-Schrieffer…

Quantum Gases · Physics 2022-04-08 F. Pascucci , A. Perali , L. Salasnich

We determine the effects of quantum fluctuations about the T=0 mean field solution of the BCS-BEC crossover in a dilute Fermi gas using the functional integral method. These fluctuations are described in terms of the zero point motion of…

Other Condensed Matter · Physics 2008-03-20 Roberto B. Diener , Rajdeep Sensarma , Mohit Randeria

We investigate the zero-temperature quasiparticle properties of a mobile impurity immersed in a strongly interacting Fermi superfluid at the crossover from a Bose-Einstein condensate (BEC) to a Bardeen--Cooper--Schrieffer (BCS) superfluid,…

Quantum Gases · Physics 2022-02-18 Hui Hu , Jia Wang , Jing Zhou , Xia-Ji Liu

We present a theoretical study of the density and spin (representing the two components) linear response of Fermi superfluids with tunable attractive interactions and population imbalance. In both linear response theories, we find that the…

Quantum Gases · Physics 2014-04-01 Hao Guo , Yang Li , Yan He , Chih-Chun Chien

We investigate the zero-temperature BCS to Bose-Einstein crossover at the mean-field level, by driving it with the attractive potential and the particle density.We emphasize specifically the role played by the particle density in this…

Superconductivity · Physics 2009-10-31 N. Andrenacci , A. Perali , P. Pieri , G. C. Strinati

Transition temperatures $T_{c}$ calculated using the BCS model electron-phonon interaction without any adjustable parameters agree with empirical values for quasi-2D cuprate superconductors. They follow from a two-dimensional gas of…

Superconductivity · Physics 2009-11-07 M. Casas , M. de Llano , A. Puente , A. Rigo , M. A. Solis