English
Related papers

Related papers: Theory of ultracold Fermi gases

200 papers

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

Ultracold atom gases provide model systems in which many-body quantum physics phenomena can be studied. Recent experiments on Fermi gases have realized a phase transition to a Fermi superfluid state with strong interparticle interactions.…

Other Condensed Matter · Physics 2008-09-04 J. T. Stewart , J. P. Gaebler , D. S. Jin

We review recent developments in the field of ultracold atomic Fermi gases. As the cold atom system evolves from BCS to Bose-Einstein condensation (BEC), the behavior of the thermodynamics, and the particle density profiles evolves smoothly…

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

We calculate Bardeen-Cooper-Schrieffer (BCS) state of a unitary Fermi gas of atoms interacting with the finite-ranged Jost-Kohn potential which has been recently shown to account for the resonant interactions [2019 {\rm J. Phys. B: At. Mol.…

Quantum Gases · Physics 2021-11-05 Subhanka Mal , Bimalendu Deb

A gas of interacting ultracold fermions can be tuned into a strongly interacting regime using a Feshbach resonance. Here we theoretically study quasiparticle transport in a system of two reservoirs of interacting ultracold fermions on the…

Quantum Gases · Physics 2016-09-19 Tibor Sekera , Christoph Bruder , Wolfgang Belzig

We study the superfluid state of atomic Fermi gases using a BCS-BEC crossover theory. Our approach emphasizes non-condensed fermion pairs which strongly hybridize with their (Feshbach-induced) molecular boson counterparts. These pairs lead…

Soft Condensed Matter · Physics 2011-09-13 Jelena Stajic , J. N. Milstein , Qijin Chen , M. L. Chiofalo , M. J. Holland , K. Levin

Strongly interacting, dilute Fermi gases exhibit a scale-invariant, universal thermodynamic behaviour. This is notoriously difficult to understand theoretically because of the absence of a small interaction parameter. Here we present a…

Quantum Gases · Physics 2010-08-25 Hui Hu , Xia-Ji Liu , Peter D. Drummond

Superfluidity in an ultracold Fermi gas is usually associated with either a negative scattering length, or the presence of a two-body bound state. We show that none of these ingredients is necessary to achieve superfluidity. Using a narrow…

Statistical Mechanics · Physics 2009-11-11 Bout Marcelis , Servaas Kokkelmans

We study the crossover from the Bardeen-Cooper-Shrieffer (BCS) regime to the Bose-Einstein-condensation (BEC) regime in a quasi-two-dimensional quantum gas of ultracold fermionic atoms. Using an effective two-dimensional Hamiltonian with…

Quantum Gases · Physics 2023-08-16 Jing Zhou , Tingting Shi , Xia-Ji Liu , Hui Hu , Wei Zhang

The two-species Fermi gas with attractive short-range interactions in two spatial dimensions provides a paradigmatic system for the understanding of strongly correlated Fermi superfluids in two dimensions. It is known to exhibit a BEC-BCS…

Quantum Gases · Physics 2025-01-08 S. Ramachandran , S. Jensen , Y. Alhassid

Using mean-field theory for the Bardeen-Cooper-Schriefer (BCS) to the Bose-Einstein condensate (BEC) crossover we investigate the ground state thermodynamic properties of an interacting homogeneous Fermi gas. The interatomic interactions…

Quantum Gases · Physics 2015-06-04 Santiago F. Caballero-Benitez , Rosario Paredes , Victor Romero-Rochin

We experimentally investigate the first-order correlation function of a trapped Fermi gas in the two-dimensional BEC-BCS crossover. We observe a transition to a low-temperature superfluid phase with algebraically decaying correlations. We…

Quantum Gases · Physics 2015-07-03 P. A. Murthy , I. Boettcher , L. Bayha , M. Holzmann , D. Kedar , M. Neidig , M. G. Ries , A. N. Wenz , G. Zürn , S. Jochim

The experimental realization of stable, ultracold Fermi gases near a Feshbach resonance allows to study gases with attractive interactions of essentially arbitrary strength. They extend the classic paradigm of BCS into a regime which has…

Quantum Gases · Physics 2016-08-02 W. Zwerger

We consider a gas of cold fermionic atoms having two spin components with interactions characterized by their s-wave scattering length $a$. At positive scattering length the atoms form weakly bound bosonic molecules which can be…

Superconductivity · Physics 2009-11-10 L. D. Carr , G. V. Shlyapnikov , Y. Castin

We consider a two-component Fermi gas with a contact interaction from the BCS regime to the unitary limit. Starting from the idea that many-body effects should not depend on short-distance or high-momentum physics which is encoded in the…

Quantum Gases · Physics 2021-06-15 M. Urban , S. Ramanan

A new mechanism is proposed to explain the puzzling damping of collective excitations, which was recently observed in the experiments of strongly interacting Fermi gases below the superfluid critical temperature on the fermionic (BCS) side…

Quantum Gases · Physics 2011-03-01 Zixu Zhang , W. Vincent Liu

This is an introductory lecture to the theory of degenerate Fermi gases, in the context of present experiments on atomic Fermi gases. In part one, some properties of the ideal Fermi gas are presented, including a discussion of the…

Other Condensed Matter · Physics 2009-03-02 Yvan Castin

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 perform a variational quantum Monte Carlo simulation of the transition from a Bardeen-Cooper-Schrieffer superfluid (BCS) to a Bose-Einstein condensate (BEC) at zero temperature. The model Hamiltonian involves an attractive short range…

Other Condensed Matter · Physics 2008-12-01 R. Jauregui , R. Paredes , L. Rosales-Zarate , G. Toledo Sanchez

Understanding the rich behavior that emerges from systems of interacting quantum particles, such as electrons in materials, nucleons in nuclei or neutron stars, the quark-gluon plasma, and superfluid liquid helium, requires investigation of…