7 research outputs found
Nonuniform mixed-parity superfluid state in Fermi gases
We study the effects of dipole interaction on the superfluidity in a
homogeneous Fermi gas with population imbalance. We show that the
Larkin-Ovchinnikov-Fulde-Ferrell phase is replaced by another nonuniform
superfluid phase, in which the order parameter has a nonzero triplet component
induced by the dipole interaction.Comment: 4 pages, 1 figur
Quantum fluctuations in Larkin-Ovchinnikov-Fulde-Ferrell superconductors
We study the superconducting order parameter fluctuations near the phase
transition into the Larkin-Ovchinnikov-Fulde-Ferrell state in the clean limit
at zero temperature. In contrast to the usual normal metal-to-uniform
superconductor phase transition, the fluctuation corrections are dominated by
the modes with the wave vectors away from the origin. We find that the
superconducting fluctuations lead to a divergent spin susceptibility and a
breakdown of the Fermi-liquid behavior at the quantum critical point.Comment: 10 pages, 4 figure
Superconducting fluctuation corrections to ultrasound attenuation in layered superconductors
We consider the temperature dependence of the sound attenuation and sound
velocity in layered impure metals due to superconducting fluctuations of the
order parameter above the critical temperature. We obtain the dependence on
material properties of these fluctuation corrections in the hydrodynamic limit,
where the electron mean free path is much smaller than the wavelength of sound
and where the electron collision rate is much larger than the sound frequency.
For longitudinal sound propagating perpendicular to the layers, the open Fermi
surface condition leads to a suppression of the divergent contributions to
leading order, in contrast with the case of paraconductivity. The leading
temperature dependent corrections, given by the Aslamazov-Larkin, Maki-Thompson
and density of states terms, remain finite as T->Tc. Nevertheless, the
sensitivity of new ultrasonic experiments on layered organic conductors should
make these fluctuations effects measurable.Comment: 13 pages, 6 figures. Accepted for PRB. Added discussion on incoherent
interlayer tunneling and other small modifications suggested by referee
Superfluid pairing in a polarized dipolar Fermi gas
We calculate the critical temperature of a superfluid phase transition in a
polarized Fermi gas of dipolar particles. In this case the order parameter is
anisotropic and has a nontrivial energy dependence. Cooper pairs do not have a
definite value of the angular momentum and are coherent superpositions of all
odd angular momenta. Our results describe prospects for achieving the
superfluid transition in single-component gases of fermionic polar molecules.Comment: 12 pages, 2 figure