Related papers: BCS-BEC crossover with unequal mass fermions
We experimentally determined various thermodynamic quantities of interacting two-component fermions at the zero-temperature limit from the Bardeen-Cooper-Schrieffer (BCS) region to the unitarity limit. The obtained results are very accurate…
We investigate the zero-temperature properties of a dilute two-component Fermi gas with attractive interspecies interaction in the BCS-BEC crossover. We build an efficient parametrization of the energy per particle based on Monte Carlo data…
We briefly discuss recent experiments on the BCS-BEC crossover with ultracold alkali-metal atoms both in three-dimensional configurations and two-dimensional ones. Then we analyze the quantum-field-theory formalism used to describe an…
We study the effects of many-body correlations in trapped ultracold atomic Bose gases. We calculate the ground state of the gas using a ground-state auxiliary-field quantum Monte Carlo (QMC) method [Phys. Rev. E 70, 056702 (2004)]. We…
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…
We show that the Bardeen-Cooper-Schrieffer state (BCS) and the Bose-Einstein condensation (BEC) sides of the BCS-BEC crossover can be rigorously distinguished from each other by the extrema of the spectrum of the fermionic excitations.…
We present a measurement of the potential energy of an ultracold trapped gas of $^{40}$K atoms in the BCS-BEC crossover and investigate the temperature dependence of this energy at a wide Feshbach resonance, where the gas is in the…
We theoretically investigate the Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensation (BEC) crossover in a two-dimensional Fermi gas with the finite-range interaction by using the Hartree-Fock-Bogoliubov theory. Expanding the…
We investigate here the BCS BEC crossover in relativistic systems using a variational construct for the ground state and the minimization of the thermodynamic potential. This is first studied in a four fermion point interaction model and…
We precisely measured the binding energy of a molecular state near the Feshbach resonance in a $^{85}$Rb Bose-Einstein condensate (BEC). Rapid magnetic field pulses induced coherent atom-molecule oscillations in the BEC. We measured the…
We investigate a mix-dimensional Fermi-Fermi mixture in which one species is confined in two-dimensional(2D) space while the other is free in three-dimensional space(3D). We determine the superfluid transition temperature $T_{c}$ for the…
We analyse the scattering rate of an impurity atom in a Fermi sea as a function of momentum and temperature in the BCS-BEC crossover. The cross section is calculated using a microscopic multichannel theory for the Feshbach resonance…
We study the free expansion of a dilute two-component Fermi gas with attractive interspecies interaction in the BCS-BEC crossover. We apply a time-dependent parameter-free density-functional theory by using two choices of the equation of…
We have observed condensation of fermionic atom pairs in the BCS-BEC crossover regime. A trapped gas of fermionic 40K atoms is evaporatively cooled to quantum degeneracy and then a magnetic-field Feshbach resonance is used to control the…
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…
We address theoretically the puzzling discontinuity of the radial quadrupole mode frequency observed in a trapped Fermi gas across the BEC-BCS crossover. We apply the scaling transformation to a two-channel model of a resonant Fermi…
We present an overview of our recent measurements on the crossover from a Bose-Einstein condensate of molecules to a Bardeen-Cooper-Schrieffer superfluid. The experiments are performed on a two-component spin-mixture of $^6$Li atoms, where…
The effect of particle-hole fluctuations for the BCS-BEC crossover is investigated by use of functional renormalization. We compute the critical temperature for the whole range in the scattering length $a$. On the BCS side for small…
We investigate a two-component Fermi gas with unequal spin populations along the BCS-BEC crossover. By using the extended BCS equations and the concept of off-diagonal-long-range-order we derive a formula for the condensate number of Cooper…
The energy spectrum for three species of identical fermionic atoms close to a Feshbach resonance is computed by use of a nonperturbative flow equation. Already a simple truncation shows that for large scattering length $|a|$ the lowest…