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Related papers: BEC-BCS Crossover in the Epsilon Expansion

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We study the BCS-BEC crossover phenomenon of triplet exciton condensation using a half-filled bilayer Hubbard model. We calculate the dynamical spin structure factor and the exciton wave function on the phase boundary between the…

Strongly Correlated Electrons · Physics 2023-06-21 Hidemaro Suwa , Shang-Shun Zhang , Cristian D. Batista

We theoretically study the thermodynamic properties of a strongly interacting Fermi gas at the crossover from a Bardeen-Cooper-Schrieffer (BCS) superfluid to a Bose-Einstein condensate (BEC), by applying a recently outlined strong-coupling…

Quantum Gases · Physics 2022-01-14 Brendan C. Mulkerin , Xing-Can Yao , Yoji Ohashi , Xia-Ji Liu , Hui Hu

We calculate the pair correlation function and the order parameter correlation function, which probe, respectively, the intra-pair and inter-pair correlations of a Fermi gas with attractive inter-particle interaction, in terms of a…

Superconductivity · Physics 2014-06-18 F. Palestini , G. C. Strinati

The authors of a recent paper (PRA \textbf{87}, 013613 (2013)) argued that in fermionic systems with d-wave pairing the speed of sound is nonanalytic across the BCS-BEC crossover at the point where the chemical potential vanishes,…

Strongly Correlated Electrons · Physics 2016-06-29 Zlatko Koinov , Rafael Mendoza

The non-relativistic $G_0 G$ formalism of BCS-BEC crossover at finite temperature is extended to relativistic fermion systems. The uncondensed pairs contribute a pseudogap to the fermion excitations. The theory recovers the BCS mean field…

High Energy Physics - Phenomenology · Physics 2008-11-26 Lianyi He , Pengfei Zhuang

We address theoretically the puzzling discontinuity of the radial quadrupole mode frequency observed in a trapped Fermi gas across the BEC-BCS crossover. We apply the scaling transformation to a two-channel model of a resonant Fermi…

Quantum Gases · Physics 2025-06-02 Sergueï V. Andreev

We study the expansion behaviours of a Fermionic superfluid in a cigar-shaped optical dipole trap for the whole BEC-BCS crossover and various temperatures. At low temperature ($0.06(1) T_F$), the atom cloud undergoes an anisotropic…

Feshbach scattering resonances are being utilized in atomic gases to explore the entire crossover region from a Bose-Einstein Condensation (BEC) of composite bosons to a Bardeen-Cooper-Schrieffer (BCS) of Cooper pairs. Several theoretical…

Superconductivity · Physics 2009-11-10 S. De Palo , M. L. Chiofalo , M. J. Holland , S. J. J. M. F. Kokkelmans

The Josephson current-phase characteristics, that arise when a supercurrent flows across two fermionic superfluids separated by a potential barrier, can be controlled by varying either the inter-particle coupling or the temperature. While…

Superconductivity · Physics 2020-10-21 Verdiana Piselli , Stefano Simonucci , Giancarlo Calvanese Strinati

We study the shear viscosity of a dilute Fermi gas as a function of the scattering length in the vicinity of the unitarity limit. The calculation is based on kinetic theory, which provides a systematic approach to transport properties in…

Quantum Gases · Physics 2014-12-17 Marcus Bluhm , Thomas Schaefer

We study the field theory for the SU($N_c$) symmetric antiferromagnetic quantum critical metal with a one-dimensional Fermi surface embedded in general space dimensions between two and three. The asymptotically exact solution valid in this…

Strongly Correlated Electrons · Physics 2018-08-29 Andres Schlief , Peter Lunts , Sung-Sik Lee

We review the study of the superfluid phase transition in a system of fermions whose interaction can be tuned continuously along the crossover from Bardeen-Cooper-Schrieffer (BCS) superconducting phase to a Bose-Einstein condensate (BEC),…

Quantum Gases · Physics 2021-05-06 Luca Dell'Anna , Stefano Grava

We elucidate the role of the effective range in the Bose-Einstein-condensate (BEC) to Bardeen-Cooper-Schrieffer (BCS) crossover regime of two-component fermions in three dimensions. In contrast to ultracold Fermi gases near the broad…

Quantum Gases · Physics 2023-05-01 Hiroyuki Tajima , Haozhao Liang

We show that the DC Josephson effect with ultracold fermionic gases in the BEC regime of composite molecules can be described by a nonlinear Schrodinger equation (NLSE). By comparing our results with Bogoliubov-de Gennes calculations [Phys.…

Other Condensed Matter · Physics 2009-11-13 F. Ancilotto , L. Salasnich , F. Toigo

The subject of BCS - Bose Einstein condensation (BEC) crossover is particularly exciting because of its realization in ultracold Fermi gases and its possible relevance to high temperature superconductors. In the paper we review that body of…

Other Condensed Matter · Physics 2015-05-13 K. Levin , Qijin Chen , Chih-Chun Chien , Yan He

It is shown that a cluster expansion technique, which is usually applied in the high-temperature regime to calcutate virial coefficients, can be applied to evaluate the superfluid transition temperature of the BCS-BEC crossover \`a la Lee…

Quantum Gases · Physics 2014-03-19 Naoyuki Sakumichi , Yusuke Nishida , Masahito Ueda

We investigate the superfluid phase transition and effects of mass imbalance in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover regime of an cold Fermi gas. We point out that the Gaussian fluctuation theory…

Quantum Gases · Physics 2013-07-11 Ryo Hanai , Takashi Kashimura , Ryota Watanabe , Daisuke Inotani , Yoji Ohashi

We review efforts to unify both the Bardeen, Cooper and Schrieffer (BCS) and Bose-Einstein condensation (BEC) pictures of superconductivity. We have finally achieved this in terms of a "\textit{complete} boson-fermion (BF) model" (CBFM)…

Superconductivity · Physics 2007-05-23 J. Batle , M. Casas , M. Fortes , M. de Llano , O. Rojo , F. J. Sevilla , M. A. Solis , V. V. Tolmachev

Many-body effects may influence properties, such as scattering parameters, nature of pairing, etc., close to a Feshbach resonance in the fermion BEC-BCS crossover problem. We study effects such as these using a tractable crossing-symmetric…

Quantum Gases · Physics 2015-06-05 Renyuan Liao , Khandker F. Quader

We consider the current correlation function for a three-dimensional system of fermions embedded in a homogeneous background and mutually interacting via an attractive short-range potential, below the (superconducting) critical temperature.…

Superconductivity · Physics 2009-11-10 N. Andrenacci , P. Pieri , G. C. Strinati