English
Related papers

Related papers: BCS-BEC crossover-like phenomena driven by quantum…

200 papers

We investigate single-particle excitations and strong-coupling effects in the BCS-BEC crossover regime of a superfluid Fermi gas. Including phase and amplitude fluctuations of the superfluid order parameter within a $T$-matrix theory, we…

Quantum Gases · Physics 2015-05-19 Ryota Watanabe , Shunji Tsuchiya , Yoji Ohashi

Superfluidity in fermionic systems originates from pairing of fermions, and Bose condensation of these so-called Cooper pairs. The Cooper pairs are usually made of fermions of different species; for example in superconductors they are pairs…

Superconductivity · Physics 2013-06-20 Kun Yang

We discuss the effect of a molecular Bose condensate on the energy of Fermi excitations in a trapped two-component atomic Fermi gas. The single-particle Green's functions can be approximated by the well-known BCS form, in both the BCS…

Soft Condensed Matter · Physics 2016-08-31 Y. Ohashi , A. Griffin

We present a theory of a degenerate atomic Fermi gas, interacting through a narrow Feshbach resonance, whose position and therefore strength can be tuned experimentally, as demonstrated recently in ultracold trapped atomic gases. The…

Superconductivity · Physics 2007-05-23 V. Gurarie , L. Radzihovsky

The main focus of this paper is a discussion of what might happen in a BCS superfluid when there is an imbalance between the two populations of fermionic particles forming Cooper pairs, having in mind the case of ultracold Fermi gases. In…

Superconductivity · Physics 2007-05-23 R. Combescot

We present a numerical study of the one-dimensional BCS-BEC crossover of a spin-imbalanced Fermi gas. The crossover is described by the Bose-Fermi resonance model in a real space representation. Our main interest is in the behavior of the…

Quantum Gases · Physics 2013-05-29 F. Heidrich-Meisner , A. E. Feiguin , U. Schollwoeck , W. Zwerger

We study the macroscopic quantum self-trapping effect in a mixture of Bose-Einstein condensate and a large number of quantum degenerate fermions, trapped in a double-well potential with a variable separation between the wells. The large…

Other Condensed Matter · Physics 2008-03-31 S. F. Caballero Benitez , E. A. Ostrovskaya , M. Gulacsi , Yu. S. Kivshar

The recent experimental realization of spin-orbit coupling for ultra-cold atoms has generated much interest in the physics of spin-orbit coupled degenerate Fermi gases. Although recently the BCS-BEC crossover in three-dimensional (3D)…

Quantum Gases · Physics 2012-01-05 Gang Chen , Ming Gong , Chuanwei Zhang

We show that two new intra-species P-wave superfluid phases appear in two-component asymmetric Fermi systems with short-range S-wave interactions. In the BEC limit, phonons of the molecular BEC induce P-wave superfluidity in the excess…

Other Condensed Matter · Physics 2007-05-23 Aurel Bulgac , Michael McNeil Forbes , Achim Schwenk

By an exact numerical calculation of the BCS pair wavefunction and the density correlation functions both between atoms in the same and in different spin states, we extract the spatial large distance behavior of the respective functions.…

Quantum Gases · Physics 2020-04-01 J. C. Obeso-Jureidini , V. Romero-Rochin

We investigate the effects of pairing fluctuations in fermionic superfluids/superconductors where pairing occurs among three species (colors) of fermions. Such color superfluids/superconductors can be realized in three-component atomic…

Nuclear Theory · Physics 2013-09-19 Jinyi Pang , Jincheng Wang , Lianyi He

This review is written at the time of the twentieth anniversary of the discovery of high temperature superconductors, which, nearly coincides with the important discovery of the superfluid phases of ultracold trapped fermionic atoms. We…

Superconductivity · Physics 2011-09-13 Qijin Chen , Jelena Stajic , K. Levin

A debated issue in the physics of the BCS-BEC crossover with trapped Fermi atoms is to identify characteristic properties of the superfluid phase. Recently, a condensate fraction was measured on the BCS side of the crossover by sweeping the…

Superconductivity · Physics 2007-05-23 A. Perali , P. Pieri , G. C. Strinati

For the Cooper/BCS model interaction in superconductors (SCs) it is shown: a) how BCS-Bose crossover picture transition temperatures Tc, defined self-consistently by both the gap and fermion-number equations, require unphysically large…

Superconductivity · Physics 2007-05-23 M. de Llano , F. J. Sevilla , M. A. Solis , J. J. Valencia

We derive a path-integral description of the vortex state of a fermionic superfluid in the crossover region between the molecular condensate (BEC) regime and the Cooper pairing (BCS) regime. This path-integral formalism, supplemented by a…

Other Condensed Matter · Physics 2016-08-31 J. Tempere , M. Wouters , J. T. Devreese

The (mean field based) BCS theory is considered one of the most successful theories in condensed matter physics. It is justified in ordinary metal superconductors the coherence length $\xi$ is large, with two important features: the order…

Superconductivity · Physics 2018-01-22 Qijin Chen

Based on a simple model of a layered superconductor with strong attractive interaction, we find that the separation of the pair-condensation temperature from the pair-formation temperature becomes more remarkable as the interlayer hopping…

Superconductivity · Physics 2018-11-20 Kyosuke Adachi , Ryusuke Ikeda

We investigate the dimensional crossover from three to two dimensions in an ultracold Fermi gas across the whole BCS-BEC crossover. Of particular interest is the strongly interacting regime as strong correlations are more pronounced in…

Quantum Gases · Physics 2021-03-23 Bruno M. Faigle-Cedzich , Jan M. Pawlowski , Christof Wetterich

We study the nature of superfluid pairing in imbalanced Fermi mixtures in two spatial dimensions. We present evidence that the combined effect of Fermi surface mismatch and order parameter fluctuations of the superfluid condensate can lead…

Quantum Gases · Physics 2014-04-22 Philipp Strack , Pawel Jakubczyk

In this paper, we study the effect of population imbalance and its interplay with pairing strength and lattice effect in atomic Fermi gases in a one-dimensional optical lattice. We compute various phase diagrams as the system undergoes…

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