Related papers: Density and spin response functions in ultracold f…
The main focus of this paper is a discussion of what might happen in a BCS superfluid when there is an imbalance between the two populations of fermionic particles forming Cooper pairs, having in mind the case of ultracold Fermi gases. In…
We investigate the BCS-BEC crossover in three dimensional degenerate Fermi gases in the presence of spin-orbit coupling (SOC) and Zeeman field. We show that the superfluid order parameter destroyed by a large Zeeman field can be restored by…
We perform a detailed study of the collective mode across the whole BEC-BCS crossover in fermionic gases at zero temperature, covering the whole range of energy beyond the linear regime. This is done on the basis of the dynamical BCS model.…
Ultracold atomic gases and low-density neutron matter are unique in that they exhibit pairing gaps comparable to the Fermi energy which in this sense are the largest in the laboratory and in nature, respectively. This strong pairing regime,…
This article reviews recent experimental and theoretical progress on many-body phenomena in dilute, ultracold gases. Its focus are effects beyond standard weak-coupling descriptions, like the Mott-Hubbard-transition in optical lattices,…
The behavior of a dilute two-component superfluid Fermi gas subjected to rotation is investigated within the context of a weak-coupling BCS theory. The microscopic properties at finite temperature are obtained by iterating the Bogoliubov-de…
We elucidate the role of the effective range in the Bose-Einstein-condensate (BEC) to Bardeen-Cooper-Schrieffer (BCS) crossover regime of two-component fermions in three dimensions. In contrast to ultracold Fermi gases near the broad…
We investigate the superfluidity of attractive Fermi gas in a square optical lattice with spin-orbit coupling (SOC). We show that the system displays a variety of new filling-dependent features. At half filling, a quantum phase transition…
We theoretically investigate magnetic properties of a trapped ultracold Fermi gas. Including pairing fluctuations within the framework of an extended $T$-matrix approximation (ETMA), as well as effects of a harmonic trap in the local…
We explore novel features of a nonrelativistic fermionic superfluid in which the pairing interaction includes a contribution from the exchange of a dynamical bosonic mode. We show that the dynamical boson exchange (DBE), which causes a…
We study resonantly-paired s-wave superfluidity in a degenerate gas of two species (hyperfine states labeled by $\uparrow,\downarrow$) of fermionic atoms when the numbers $N_{\uparrow}$ and $N_{\downarrow}$ of the two species are {\it…
We study translation-invariant quasi-free states for a system of fermions with two-particle interactions. The associated energy functional is similar to the BCS functional but includes also direct and exchange energies. We show that for…
We present our experimental setup to produce ultracold strongly correlated fermionic superfluids made of a two-component spin-mixture of $^6$Li atoms. Employing standard cooling techniques, we achieve quantum degeneracy in a single-beam…
The non-relativistic $G_0 G$ formalism of BCS-BEC crossover at finite temperature is extended to relativistic fermion systems. The uncondensed pairs contribute a pseudogap to the fermion excitations. The theory recovers the BCS mean field…
The BCS-like pairing in ultracold fermionic atomic ($UCFAG$) gases is studied in the model of "isotopic-spin" pairing proposed in 1991 \cite% {Ku-Hof-SSC}. This model assumes a mismatch ($\delta $) in chemical potentials of pairing…
Recent experimental progresses allow for exploring some important physical quantities of ultracold Fermi gases, such as the compressibility, spin susceptibility, viscosity, optical conductivity and spin diffusivity. Theoretically, these…
Spin-orbit coupled ultra-cold atoms provide an intriguing new avenue for the study of rich spin dynamics in superfluids. In this Letter, we observe Zitterbewegung, the simultaneous velocity (thus position) and spin oscillations, of neutral…
We study the dynamics of counterflowing bosonic and fermionic lithium atoms. First, by tuning the interaction strength we measure the critical velocity vc of the system in the BEC-BCS crossover in the low temperature regime and we compare…
We investigate the behavior of dark solitons in a superfluid Fermi gas along the BCS-BEC crossover by solving the Bogoliubov - de Gennes equations and looking for real and odd solutions for the order parameter. We show that in the resonance…
We discuss the superfluid wave function of an atomic Fermi gas, which can be measured in an atom shot noise correlation experiment. We note that it is qualitatively different in the BCS and Bose limits and on the basis of this we propose…