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Related papers: Pairing fluctuations in trapped Fermi gases

200 papers

In a trapped atomic Fermi gas, one can tune continuously via a Feshbach resonance the effective pairing interaction between fermionic atoms from very weak to very strong. As a consequence, the low temperature superfluidity evolves…

Quantum Gases · Physics 2011-01-17 Yi Yu , Qijin Chen

We study the order parameter phase fluctuation effects in cuprate superconductors near T=0, using a quasi-two-dimensional d-wave BCS model. An effective phason theory is obtained which is used to estimate the strength of the fluctuations,…

Superconductivity · Physics 2009-10-31 Hyok-Jon Kwon , Alan T. Dorsey , P. J. Hirschfeld

In this letter, we investigate the fluctuation effects on the transport properties of unitary Fermi gases in the vicinity of the superfluid transition temperature $T_c$. Based on the time-dependent Ginzburg-Landau formalism of the BEC-BCS…

Quantum Gases · Physics 2014-12-17 Boyang Liu , Hui Zhai , Shizhong Zhang

We study the phase fluctuations in the normal state of generic two-dimensional superconducting systems with s-wave pairing. The effect of phase fluctuations of the pairing fields can be dealt with perturbatively using disorder averaging,…

Superconductivity · Physics 2023-06-02 Xu-Cheng Wang , Yang Qi

We study the superfluid behavior of ultracold atomic Fermi gases with a short range attractive interaction in a two-dimensional optical lattice (2DOL) using a pairing fluctuation theory, within the context of BCS-BEC crossover. We find that…

Quantum Gases · Physics 2022-03-01 Lin Sun , Jibiao Wang , Xiang Chu , Qijin Chen

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

We reveal a strong influence of a superfluid phase transition on the character of single-particle excitations of a trapped neutral-atom Fermi gas. Below the transition temperature the presence of a spatially inhomogeneous order parameter…

Statistical Mechanics · Physics 2009-10-31 M. A. Baranov

A description of mesoscopic fluctuations of the pairing gap in finite-sized quantum systems based on periodic orbit theory is presented. The size of the fluctuations are found to depend on quite general properties. We distinguish between…

Nuclear Theory · Physics 2011-04-11 S. Åberg , H. Olofsson , P. Leboeuf

We investigate the superfluid phase transition in a gas of Fermi atoms loaded on a three-dimensional optical lattice. When the lattice potential is strong, this system can be well described by an attractive Hubbard model. In this model, we…

Materials Science · Physics 2008-03-17 H. Tamaki , Y. Ohashi , K. Miyake

The pairing and superfluid phenomena in a two-component Fermi gas can be strongly affected by the population and mass imbalances. Here we present phase diagrams of atomic Fermi gases as they undergo BCS--Bose-Einstein condensation (BEC)…

Quantum Gases · Physics 2014-04-24 Jibiao Wang , Hao Guo , Qijin Chen

Single-particle spectra are calculated in the superconducting state for a fermionic system with an attractive interaction, as functions of temperature and coupling strength from weak to strong. The fermionic system is described by a…

Superconductivity · Physics 2007-05-23 P. Pieri , L. Pisani , G. C. Strinati

We investigate pseudogap phenomena in the unitarity limit of a trapped superfluid Fermi gas. Including effect of strong pairing fluctuations within a $T$-matrix approximation, as well as effects of a harmonic trap within the local density…

Quantum Gases · Physics 2015-05-28 Ryota Watanabe , Shunji Tsuchiya , Yoji Ohashi

We show that in small and low density systems described by a lattice gas model with fixed number of particles the location of a thermodynamic phase transition can be detected by means of the distribution of the fluctuations related to an…

Nuclear Theory · Physics 2009-11-07 J. M. Carmona , J. Richert , P. Wagner

We present detailed measurements of the frequency and damping of three different collective modes in an ultracold trapped Fermi gas of $^6$Li atoms with resonantly tuned interactions. The measurements are carried out over a wide range of…

Ultracold atomic Fermi gases present an opportunity to study strongly interacting Fermi systems in a controlled and uncomplicated setting. The ability to tune attractive interactions has led to the discovery of superfluidity in these…

Quantum Gases · Physics 2010-07-29 J. P. Gaebler , J. T. Stewart , T. E. Drake , D. S. Jin , A. Perali , P. Pieri , G. C. Strinati

In weakly coupled BCS superconductors, only electrons within a tiny energy window around the Fermi energy, $E_F$, form Cooper pairs. This may not be the case in strong coupling superconductors such as cuprates, FeSe, SrTiO$_3$ or cold atom…

Superconductivity · Physics 2023-06-05 Chandan Setty , Laura Fanfarillo , P. J. Hirschfeld

We theoretically investigate magnetic properties of a unitary Fermi gas in a harmonic trap. Including strong pairing fluctuations within the framework of an extended $T$-matrix approximation (ETMA), as well as effects of a trap potential…

Quantum Gases · Physics 2016-01-27 Hiroyuki Tajima , Ryo Hanai , Yoji Ohashi

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

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 low energy collective excitations in a trapped superfluid Fermi gas, that describe slow variations of the phase of the superfluid order parameter. Well below the critical temperature the corresponding eigenfrequencies turn out to…

Statistical Mechanics · Physics 2009-10-31 M. A. Baranov , D. S. Petrov