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Related papers: The critical velocity in the BEC-BCS crossover

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The character change of a superfluid state due to the variation of the attractive force is investigated in the relativistic framework with a massive fermion. Two crossovers are found. One is a crossover from the usual BCS state to the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Yusuke Nishida , Hiroaki Abuki

We study soliton collisions and the decay of solitons into sound in superfluid Fermi gases across the Bose-Einstein condensate to Bardeen-Cooper-Schrieffer (BEC-BCS) crossover by performing numerical simulations of the time-dependent…

Quantum Gases · Physics 2012-02-27 R. G. Scott , F. Dalfovo , L. P. Pitaevskii , S. Stringari , O. Fialko , R. Liao , J. Brand

We study the critical temperature of the superfluid phase transition of strongly-interacting fermions in the crossover regime between a Bardeen-Cooper-Schrieffer (BCS) superconductor and a Bose-Einstein condensate (BEC) of dimers. To this…

Quantum Gases · Physics 2024-10-16 D. Eberz , M. Link , A. Kell , M. Breyer , K. Gao , M. Köhl

We investigate the specific heat at constant volume $C_V$ in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover regime of an ultracold Fermi gas above the superfluid phase transition temperature $T_{\rm c}$.…

Quantum Gases · Physics 2016-02-03 Pieter van Wyk , Hiroyuki Tajima , Ryo Hanai , Yoji Ohashi

We use classical field simulations of the homogeneous Bose gas to study the breakdown of superflow due to vortex nucleation past a cylindrical obstacle at finite temperature. Thermal fluctuations modify the vortex nucleation from the…

Quantum Gases · Physics 2016-02-26 G. W. Stagg , R. W. Pattinson , C. F. Barenghi , N. G. Parker

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

The final stage of Bose-Einstein condensation in a large volume occurs through coarsening--growth of individual correlated patches. We present analytical arguments and numerical evidence that in the momentum space this growth corresponds to…

High Energy Physics - Phenomenology · Physics 2009-11-07 S. Khlebnikov

We analyze the theoretical derivation of the beyond-mean-field equation of state for a two-dimensional gas of dilute, ultracold alkali-metal atoms in the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensate (BEC) crossover. We show…

Quantum Gases · Physics 2018-07-24 G. Bighin , L. Salasnich

We demonstrate the existence of supersonic bell soliton in the Bardeen-Cooper-Schrieffer-Bose-Einstein condensate (BCS-BEC) crossover regime. Starting from the extended Thomas-Fermi density functional theory of superfluid order parameter, a…

Quantum Gases · Physics 2013-05-13 Ayan Khan , Prasanta K Panigrahi

A Bose-Einstein condensate (BEC) with periodically modulated interactions (PMI) has emerged as a novel kind of periodic superfluid, which has been recently experimentally created using optical Feshbach resonance. In this paper, we are…

Quantum Gases · Physics 2014-12-16 Lei Chen , Wu Li , Zhu Chen , Zhidong Zhang , Zhaoxin Liang

We study properties of excited states of an elongated Fermi superfluid along the BEC-BCS crossover including the unitarity limit. Analytic expressions for the sound velocity in an inhomogeneous as well as homogeneous Fermi superfluid along…

Superconductivity · Physics 2007-05-23 Tarun Kanti Ghosh , Kazushige Machida

The flow of a uniform Bose gas at speeds greater than the Landau critical velocity, v_c, does not necessarily destroy superfluidity, but rather need only lead to a decrease of the superfluid mass density, {\rho}_s. Analyzing a weakly…

Quantum Gases · Physics 2015-06-05 Gordon Baym , C. J. Pethick

We study expansion of quasi-one-dimensional Bose-Einstein condensate (BEC) after switching off the confining harmonic potential. Exact solution of dynamical equations is obtained in framework of the hydrodynamic approximation and it is…

Soft Condensed Matter · Physics 2009-11-10 V. A. Brazhnyi , A. M. Kamchatnov , V. V. Konotop

We describe high-Tc superconductivity in layered materials within a BCS theory as a BEC of massless-like Cooper pairons satisfying a linear dispersion relation, and propagating within quasi-2D layers of finite width defined by the charge…

Superconductivity · Physics 2017-08-23 C. Villarreal , M. de Llano

Ultracold atomic gases are a powerful tool to experimentally study strongly correlated quantum many-body systems. In particular, ultracold Fermi gases with tunable interactions have allowed to realize the famous BEC-BCS crossover from a…

We investigate the excitation spectrum and compressibility of a dipolar Bose-Einstein condensate in an infinite tube potential in the parameter regime where the transition between superfluid and supersolid phases occurs. Our study focuses…

Quantum Gases · Physics 2023-10-02 P. B. Blakie , L. Chomaz , D. Baillie , F. Ferlaino

The critical BEC temperature $T_{c}$ of a non interacting boson gas in a layered structure like those of cuprate superconductors is shown to have a minimum $T_{c,m}$, at a characteristic separation between planes $a_{m}$. It is shown that…

Quantum Gases · Physics 2015-05-14 P. Salas , M. Fortes , M. de Llano , F. J. Sevilla , M. A. Solis

Dilute gas Bose-Einstein condensates (BEC's), currently used to cool fermionic atoms in atom traps, can also probe the superfluidity of these fermions. The damping rate of BEC-acoustic excitations (phonon modes), measured in the middle of…

Other Condensed Matter · Physics 2015-06-25 Sergio Gaudio , B. Mihaila , K. B. Blagoev , K. S. Bedell , Eddy Timmermans

We derive a generalized time-dependent Galilean-invariant density-functional (DF) equation appropriate to study the stationary and non-stationary properties of a trapped Fermi super-fluid in the Bardeen-Cooper-Schrieffer (BCS) to…

Quantum Gases · Physics 2015-05-18 S. K. Adhikari

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