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Related papers: Local-field Theory of the BCS-BEC Crossover

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In this paper we construct an effective field theory for a condensate of cold Fermi atoms whose scattering is controlled by a narrow Feshbach resonance. We show how, from first principles, it permits a hydrodynamic description of the…

Superconductivity · Physics 2012-01-18 Chi-Yong Lin , Da-Shin Lee , Ray J. Rivers

We investigate strong-coupling superfluidity in a uniform gas of Fermi atoms attractively interacting via quasi-molecular bosons associated with a Feshbach resonance. This interaction is tunable by the threshold energy $2\nu$ of the…

Soft Condensed Matter · Physics 2009-11-10 Y. Ohashi , A. Griffin

We investigate the crossover from Bardeen-Cooper-Schrieffer (BCS) superfluidity to Bose-Einstein condensation (BEC) in a two-dimensional Fermi gas at T=0 using the fixed-node diffusion Monte Carlo method. We calculate the equation of state…

Quantum Gases · Physics 2015-03-17 G. Bertaina , S. Giorgini

We consider atomic Fermi gases where Feshbach resonances can be used to continuously tune the system from weak to strong interaction regime, allowing to scan the whole BCS-BEC crossover. We show how a probing field transferring atoms out of…

Strongly Correlated Electrons · Physics 2009-11-10 J. Kinnunen , M. Rodriguez , P. Torma

The superfluid phases in the resonant dipolar Fermi gases are investigated by the standard mean-field theory. In contrast to the crossover from Bose-Einstein condensation (BEC) to Bardeen-Cooper-Schrieffer (BCS) superfluid in the Fermi…

Quantum Gases · Physics 2013-05-30 T. Shi , S. -H. Zou , H. Hu , C. -P. Sun , S. Yi

We discuss the possibility of a quantum phase transition in ultra-cold spin-polarized Fermi gases which exhibit a p-wave Feshbach resonance. We show that when fermionic atoms form a condensate that can be externally tuned between the BCS…

Strongly Correlated Electrons · Physics 2009-11-11 S. S. Botelho , C. A. R. Sa de Melo

We consider a dilute atomic gas of two species of fermions with unequal concentrations under a Feshbach resonance. We find that the system can have distinct properties due to the unbound fermions. The uniform state is stable only when…

Superconductivity · Physics 2009-11-11 C. -H. Pao , Shin-Tza Wu , S. -K. Yip

The functional renormalisation group is used for the BCS-BEC crossover in gases of ultracold fermionic atoms. In a simple truncation, we see how universality and an effective theory with composite bosonic di-atom states emerge. We obtain a…

Superconductivity · Physics 2009-11-13 S. Diehl , H. Gies , J. M. Pawlowski , C. Wetterich

The study of ultracold atomic Fermi gases is a rapidly exploding subject which is defining new directions in condensed matter and atomic physics. Quite generally what makes these gases so important is their remarkable tunability and…

Quantum Gases · Physics 2012-02-13 K. Levin , Randall G. Hulet

The physics of quantum degenerate Fermi gases in uniform as well as in harmonically trapped configurations is reviewed from a theoretical perspective. Emphasis is given to the effect of interactions which play a crucial role, bringing the…

Other Condensed Matter · Physics 2009-11-13 Stefano Giorgini , Lev P. Pitaevskii , Sandro Stringari

We present a theory of a two-component atomic Fermi gas with tunable attractive contact interactions on a spherical shell going through the Bardeen-Cooper-Schrieffer (BCS) - Bose Einstein condensation (BEC) crossover, inspired by the…

Quantum Gases · Physics 2022-04-01 Yan He , Hao Guo , Chih-Chun Chien

Theoretical predictions for the BCS-BEC crossover of trapped Fermi atoms are compared with recent experimental results for the density profiles of $^6$Li. The calculations rest on a single theoretical approach that includes pairing…

Superconductivity · Physics 2009-02-20 A. Perali , P. Pieri , G. C. Strinati

Thermodynamic properties of an ultracold Fermi gas in a harmonic trap are calculated within a local density approximation, using a conserving many-body formalism for the BCS to BEC crossover problem, which has been developed by Haussmann et…

Statistical Mechanics · Physics 2009-11-13 R. Haussmann , W. Zwerger

We evaluate the frequencies of collective modes and the anisotropic expansion rate of a harmonically trapped Fermi superfluid at varying coupling strengths across a Feshbach resonance driving a BCS-BEC crossover. The equations of motion for…

Statistical Mechanics · Physics 2007-05-23 Hui Hu , A. Minguzzi , Xia-Ji Liu , M. P. Tosi

In this letter we consider the superradiant phase transition of a two-component Fermi gas in a cavity across a Feshbach resonance. It is known that quantum statistics plays a crucial role for the superradiant phase transition in atomic…

Quantum Gases · Physics 2015-03-05 Yu Chen , Hui Zhai , Zhenhua Yu

We propose phase diagrams for an imbalanced (unequal number of atoms or Fermi surface in two pairing hyperfine states) gas of atomic fermions near a broad Feshbach resonance using mean field theory. Particularly, in the plane of interaction…

Strongly Correlated Electrons · Physics 2007-05-23 Hui Hu , Xia-Ji Liu

We map out the detuning-magnetization phase diagram for a ``magnetized'' (unequal number of atoms in two pairing hyperfine states) gas of fermionic atoms interacting via an s-wave Feshbach resonance (FR). For large positive FR detuning a…

Superconductivity · Physics 2009-11-11 Daniel E. Sheehy , Leo Radzihovsky

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

A three-component Fermi gas near a broad Feshbach resonance does not have a universal ground state due to the Thomas collapse, while it does near a narrow Feshbach resonance. We explore its universal phase diagram in the plane of the…

Quantum Gases · Physics 2012-12-12 Yusuke Nishida

Tunable interactions make ultracold quantum gases a unique platform for exploring hydrodynamic properties in the strongly correlated regime. Of particular interest are turbulent flows possible in the regime of high Reynolds numbers. Since…

Quantum Gases · Physics 2026-04-14 Yunxiang Liao , Andrey Grankin , Archisman Panigrahi , Victor Galitski , Leonid Levitov