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

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We discuss the BCS-BEC crossover in a degenerate Fermi gas of two hyperfine states interacting close to a Feshbach resonance. This system has quasi-molecular Bosons associated with a Feshbach resonance, and this kinds of coupled…

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

Atomic Fermi gases have been an ideal platform for simulating conventional and engineering exotic physical systems owing to their multiple tunable control parameters. Here we investigate the effects of mixed dimensionality on the superfluid…

Quantum Gases · Physics 2017-10-12 Leifeng Zhang , Yanming Che , Jibiao Wang , Qijin Chen

We report quantum Monte Carlo evidence of the existence of large gap superfluidity in electron-hole double layers over wide density ranges. The superfluid parameters evolve from normal state to BEC with decreasing density, with the BCS…

Superconductivity · Physics 2018-05-02 Pablo López Ríos , Andrea Perali , Richard J. Needs , David Neilson

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

It is generally believed that the BCS-BEC evolution in fermionic systems with s-wave pairing is a smooth crossover. However, for nonzero orbital-angular-momentum pairing such as p- or d-wave pairing, the system undergoes a quantum phase…

Quantum Gases · Physics 2013-01-15 Gaoqing Cao , Lianyi He , Pengfei Zhuang

We investigate strong coupling effects on the superfluid phase transition in a gas of Fermi atoms with a Feshbach resonance. The Feshbach resonance describes a composite quasi-Boson, which can give rise to an additional pairing interaction…

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

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

We study finite-temperature properties of a two-dimensional superfluid made of ultracold alkali-metal atoms in the BCS-BEC crossover. We investigate the region below the critical temperature $T_{BKT}$ of the Berezinskii-Kosterlitz-Thouless…

Quantum Gases · Physics 2013-11-20 L. Salasnich , P. A. Marchetti , F. Toigo

The signature of superfluidity in bosonic systems is a sound wave-like spectrum of the single particle excitations which in the case of strong interactions is roughly temperature independent. In fermionic systems, where fermion pairing…

Superconductivity · Physics 2009-11-10 T. Domanski , J. Ranninger

Fermionic many-body systems provide an unrivaled arena to investigate how interactions drive the emergence of collective quantum behavior, such as macroscopic coherence and superfluidity. Central to these phenomena is the formation of…

The effect of a quantum phase transition associated with the appearance of the fermion condensate in an electron liquid on the properties of superconductors is considered. It is shown that the electron system in both superconducting and…

Strongly Correlated Electrons · Physics 2016-08-31 M. Ya. Amusia , V. R. Shaginyan

In this paper we follow the analysis and protocols of recent experiments, combined with simple theory, to arrive at a physical understanding of quasi-condensation in two dimensional Fermi gases. We find that quasi-condensation mirrors…

Quantum Gases · Physics 2015-12-16 Chien-Te Wu , Brandon M. Anderson , Rufus Boyack , K. Levin

Resonances in the superconducting properties, in a regime of crossover from BCS to mixed Bose-Fermi superconductivity, are investigated in a two-band superconductor where the chemical potential is tuned near the band edge of the second…

We study the formation of quantum droplets in the mixture of a single-component Bose-Einstein condensate (BEC), and a two-species Fermi superfluid across a wide Feshbach resonance. With repulsive boson-boson and attractive boson-fermion…

Quantum Gases · Physics 2020-07-07 Jing-Bo Wang , Jian-Song Pan , Xiaoling Cui , Wei Yi

Fermi systems in the crossover regime between weakly coupled Bardeen-Cooper-Schrieffer (BCS) and strongly coupled Bose-Einstein-condensate (BEC) limits are among the most fascinating objects to study the behavior of an assembly of strongly…

We offer strong evidence that the recent observations by M. Greiner, C. Regal, and D. Jin and by MIT group are signatures of a fermion superfluid in the strongly interacting regime made up of large fermion pairs. Our conclusions are based…

Superconductivity · Physics 2007-05-23 Roberto B. Diener , Tin-Lun Ho

We explore the universal properties of interacting fermionic lattice systems, mostly focusing on the development of pairing correlations from attractive interactions. Using renormalization group we identify a large number of fixed points…

Strongly Correlated Electrons · Physics 2013-05-29 Predrag Nikolic

Recent experiments have observed condensation behavior in a strongly interacting system of fermionic atoms. We interpret these observations in terms of a mean-field version of resonance superfluidity theory. We find that the objects…

Soft Condensed Matter · Physics 2009-11-10 A. V. Avdeenkov , J. L. Bohn

By using a well established 'ab initio' theoretical approach developed in the past to quantitatively study the superconductivity of condensed matter systems, which is based on the Kohn-Sham Density Functional theory, I study the superfluid…

Quantum Gases · Physics 2016-06-01 Francesco Ancilotto

We report on the observation of the Josephson effect between two strongly interacting fermionic superfluids coupled through a thin tunneling barrier. We prove that the relative population and phase are canonically conjugate dynamical…