Quantum phase transitions in disordered superconductors and detection of modulated superfluidity in imbalanced Fermi gases

Sarang Gopalakrishnan

Ben A. Olsen, Melissa Revelle, Jacob A. Fry +1 more

A. V. Syromyatnikov, F. D. Timkovskii

Heron Caldas

Abstract We investigate the superfluid-to-normal zero temperature quantum phase transitions of asymmetric two-component Fermi gases as a function of the chemical potential imbalance h . The calculations are performed for homogeneous and trapped imbalanced systems. We concentrate at unitarity, characterized by a divergent interaction parameter k F a , where most of the current experiments are realized. For homogeneous systems, we determine the critical chemical potential imbalance h c at which possible phase transitions occur. In the case of trapped gases, we show how h c can be consistently determined from experimental observations.

Heron Caldas

In this chapter the recent theoretical work on phase transition in imbalanced fermion superfluids is reviewed. The imbalanced systems are those in which the two fermionic species candidate to form pairing have different Fermi surfaces or densities. We consider systems subjected to weak interactions. In this scenario two distinct phase transitions are predicted to occur. A thermodynamical phase transition, induced by the temperature (T), and a quantum phase transition as a function of the increasing chemical potentials asymmetry, that takes place at zero temperature. We also briefly discuss some recent experimental work at non-zero T with imbalanced Fermi gases in cold atomic traps.

Heron Caldas