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Related papers: BCS-BEC crossover with unequal mass fermions

200 papers

In this letter we study the interaction energy in a mixture of Bose and Fermi superfluids realized in recent cold atom experiment. On the Bose-Einstein-condensate (BEC) side of a Feshbach resonance between fermionic atoms, this interaction…

Quantum Gases · Physics 2014-12-24 Ren Zhang , Wei Zhang , Hui Zhai , Peng Zhang

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

Trapped two-component Fermi gases allow for the investigation of the so-called BCS-BEC crossover by tuning the interspecies atom-atom $s$-wave scattering length scattering $a^{(aa)}$ from attractive to repulsive, including vanishing and…

Quantum Gases · Physics 2014-11-21 K. M. Daily , D. Blume

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

We report results of quantum Monte Carlo calculations of the ground state of dilute Fermi gases with attractive short range two-body interactions. The strength of the interaction is varied to study different pairing regimes which are…

Atomic Physics · Physics 2009-02-05 S. Y. Chang , J. Carlson , V. R. Pandharipande , K. E. Schmidt

We systematically study the BCS-BEC crossover and the quantum phase transition in ultracold 6Li and 40K atoms across a wide Feshbach resonance. The background scattering lengths for 6Li and 40K have opposite signs, which lead to very…

Other Condensed Matter · Physics 2007-05-23 W. Yi , L. -M. Duan

We analyze the phase diagram of superfluidity for two-species fermion mixtures from the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensation (BEC) limit as a function of scattering parameter, population imbalance and mass…

Superconductivity · Physics 2009-11-13 M. Iskin , C. A. R. Sa de Melo

We study s-wave superconductivity in the two dimensional attractive Hubbard model in an applied magnetic field, assume the extreme Pauli limit, and examine the role of spatial fluctuations in the coupling regime corresponding to BCS-BEC…

Quantum Gases · Physics 2016-05-26 Madhuparna Karmakar , Pinaki Majumdar

We investigate the phase diagram and the BCS-BEC crossover of a homogeneous three-component ultracold Fermi gas with a U(3) invariant attractive interaction. We show that the system at sufficiently low temperatures exhibits population…

Quantum Gases · Physics 2010-12-16 Tomoki Ozawa , Gordon Baym

We study a trapped system of fermions with a zero-range two-body interaction using the shell-model Monte Carlo method, providing {\em ab initio} results for the low particle number limit where mean-field theory is not applicable. We present…

Superconductivity · Physics 2009-09-22 N. T. Zinner , K. Mølmer , C. Özen , D. J. Dean , K. Langanke

The four-body problem for an interacting two-species Fermi gas is solved analytically in a confined quasi-one-dimensional geometry, where the two-body atom-atom scattering length $a_{aa}$ displays a confinement-induced resonance. We compute…

Statistical Mechanics · Physics 2007-05-23 C. Mora , A. Komnik , R. Egger , A. O. Gogolin

A sum rule approach is used to calculate the zero temperature oscillation frequencies of a two component trapped atomic Fermi gas in the BCS-Bose Einstein condensation crossover region. These sum rules are evaluated using a local density…

Other Condensed Matter · Physics 2007-05-23 Theja N. De Silva , Erich J. Mueller

We show that the long-distance behavior of the two-body density correlation functions and the Cooper-pair probability density of a balanced mixture of a two-component Fermi gas at $T = 0$, is universal along the BEC-BCS crossover. Our…

We analyze the BCS-BEC crossover transition of a balanced two component mixture of fermions interacting via a finite range potential, within a mean field approach. For the analysis we consider three finite range potentials cases describing…

We report the experimental measurement of the equation of state of a two-dimensional Fermi gas with attractive s-wave interactions throughout the crossover from a weakly coupled Fermi gas to a Bose gas of tightly bound dimers as the…

Quantum Gases · Physics 2016-02-02 I. Boettcher , L. Bayha , D. Kedar , P. A. Murthy , M. Neidig , M. G. Ries , A. N. Wenz , G. Zürn , S. Jochim , T. Enss

We investigate an ultracold Bose-Fermi mixture with a Feshbach resonance between two hyperfine states of fermions. Using a functional integral method, we calculate collective modes associated with fermion-pairs and bosons in a superfluid…

Other Condensed Matter · Physics 2007-06-13 Hiroyuki Shibata , Nobuhiko Yokoshi , Susumu Kurihara

We investigate the BCS-BEC crossover in a bilayer system of fermionic dipoles at zero temperature using the fixed-node diffusion Monte Carlo technique. The dipoles are confined on two parallel planes separated by a distance $\lambda$ and…

Quantum Gases · Physics 2014-11-26 Natalia Matveeva , Stefano Giorgini

We extend our previous investigations of fermionic condensation in broad Feshbach resonances by using the two-channel model developed for narrow Feshbach resonances. We investigate two crossovers: the BCS-BEC crossover by changing the…

Quantum Gases · Physics 2012-11-19 Luca Salasnich

Feshbach scattering resonances are being utilized in atomic gases to explore the entire crossover region from a Bose-Einstein Condensation (BEC) of composite bosons to a Bardeen-Cooper-Schrieffer (BCS) of Cooper pairs. Several theoretical…

Superconductivity · Physics 2009-11-10 S. De Palo , M. L. Chiofalo , M. J. Holland , S. J. J. M. F. Kokkelmans

We determine the effects on the BCS-BEC crossover of the energy dependence of the effective two-body interaction, which at low energies is determined by the effective range. To describe interactions with an effective range of either sign,…

Superconductivity · Physics 2008-11-26 L. M. Jensen , H. M. Nilsen , Gentaro Watanabe