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Related papers: Critical Temperature Curve in the BEC-BCS Crossove…

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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

It has been proposed that the superconducting transition temperature $T_{\mathrm{c}}$ of an unconventional superconductor with a large pairing scale but strong phase fluctuations can be enhanced by coupling it to a metal. However, the…

Superconductivity · Physics 2022-12-05 Philip M. Dee , Steven Johnston , Thomas Maier

The theoretical description of the critical temperature Tc of a Fermi superfluid dates back to the work by Gor'kov and Melik-Barkhudarov (GMB), who addressed it for a weakly-coupled (dilute) superfluid in the BCS (weak-coupling) limit of…

Superconductivity · Physics 2018-02-07 L. Pisani , A. Perali , P. Pieri , G. Calvanese Strinati

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

In this paper we address the question of whether high-temperature superconductors have anything in common with BCS-BEC crossover theory. Towards this goal, we present a proposal and related predictions which provide a concrete test for the…

Superconductivity · Physics 2024-03-19 Qijin Chen , Zhiqiang Wang , Rufus Boyack , K. Levin

We analyse fluctuations about $T_c$ in the specific heat of (Y,Ca)Ba$_2$Cu$_3$O$_{7-\delta}$, YBa$_2$Cu$_4$O$_8$ and Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. The mean-field transition temperature, $T_c^{mf}$, in the absence of fluctuations lies…

Superconductivity · Physics 2009-09-01 J. L. Tallon , J. G. Storey , J. W. Loram

A study of temperature dependences of the upper critical field B_{c2}(T) and surface impedance Z(T)=R(T)+iX(T) in Ba_{1-x}K_xBiO_3 single crystals that have transition temperatures in the range 6 < T_c < 32 K (roughly 0.6>x>0.4) reveals a…

We propose a method for simulating the behaviour of small clusters of particles that explicitly accounts for all mean-field and binary-correlation effects. Our approach leads to a set of variational equations that can be used to study both…

Other Condensed Matter · Physics 2009-11-11 J. N. Milstein , K. Burnett

We derive a phase diagram for the pseudogap onset temperature $T^*$ (associated with the breakdown of the Fermi liquid state, due to strong pairing correlations) and the superconducting instability, $T_c$, as a function of variable pairing…

Superconductivity · Physics 2007-05-23 Jiri Maly , Boldizsar Janko , K. Levin

A realistic description of the Josephson effect at finite temperature with ultra-cold Fermi gases embedded in nontrivial geometrical constraints (typically, a trap plus a barrier) requires appropriate consideration of pairing fluctuations…

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

We study the BCS--BEC crossover of the large $N$ attractive Fermi-Hubbard model on a one-dimensional lattice using the mean field approximation in the presence of an imaginary chemical potential. We show that the crossover is governed by…

High Energy Physics - Theory · Physics 2026-04-22 Evangelos G. Filothodoros

Superconductivity in iron-based, magnesium diborides, and other novel superconducting materials has a strong multi-band and multi-gap character. Recent experiments support the possibillity for a BCS-BEC crossover induced by strong-coupling…

Superconductivity · Physics 2014-11-05 Andrea Guidini , Andrea Perali

We perform a detailed study of the collective mode across the whole BEC-BCS crossover in fermionic gases at zero temperature, covering the whole range of energy beyond the linear regime. This is done on the basis of the dynamical BCS model.…

Other Condensed Matter · Physics 2014-11-17 R. Combescot , M. Yu. Kagan , S. Stringari

All solid phases of bismuth under pressure, but one, have been experimentally found to superconduct. From Bi-I to Bi-V, avoiding Bi-IV, they become superconductors and perhaps Bi-IV may also become superconductive. To investigate the…

We discuss an integrable model of interacting Fermions in one dimension, that allows an exact description of the crossover from a BCS- to a Bose-like superfluid. This model bridges the Gaudin-Yang model of attractive spin 1/2 Fermions to…

Statistical Mechanics · Physics 2007-05-23 J. N. Fuchs , A. Recati , W. Zwerger

We consider a two-component gas of fermionic atoms confined to a quasi-two-dimensional (quasi-2D) geometry by a harmonic trapping potential in the transverse direction. We construct a mean field theory of the BCS-BEC crossover at zero…

Quantum Gases · Physics 2014-03-04 Andrea M. Fischer , Meera M. Parish

We investigate the finite-temperature superfluid behavior of ultracold atomic Fermi gases in quasi-two-dimensional Lieb lattices with a short-range attractive interaction, using a pairing fluctuation theory within the BCS-BEC crossover…

Quantum Gases · Physics 2024-01-09 Hao Deng , Lin Sun , Chuping Li , Yuxuan Wu , Junru Wu , Qijin Chen

We present a systematic theoretical study of the BCS-BEC crossover problem in three-dimensional atomic Fermi gases at zero temperature with a spherical spin-orbit coupling which can be generated by a synthetic non-Abelian gauge field…

Quantum Gases · Physics 2012-07-13 Lianyi He , Xu-Guang Huang

Reasonably good agreement with the superconducting transition temperatures of the cuprate high-Tc superconductors can be obtained on the basis of an approximate phenomenological theory. In this theory, two criteria are used to calculate the…

Superconductivity · Physics 2007-05-23 Mario Rabinowitz , T. McMullenb

We study the dynamics of counterflowing bosonic and fermionic lithium atoms. First, by tuning the interaction strength we measure the critical velocity vc of the system in the BEC-BCS crossover in the low temperature regime and we compare…