Imbalanced ultracold Fermi gas in the weakly repulsive regime: Renormalization group approach for p-wave superfluidity

Abstract

We theoretically study a possible new pairing mechanism for a two-dimensional population imbalanced Fermi gas with short-range repulsive interactions which can be realized on the upper branch of a Feshbach resonance. We use a well-controlled renormalization group approach, which allows an unbiased study of the instabilities of imbalanced Fermi liquid without assumption of a broken symmetry and gives a numerical calculation of the transition temperature from microscopic parameters. Our results show a leading superfluid instability in the p-wave channel for the majority species. The corresponding mechanism is that there are effective attractive interactions for the majority species, induced by the particle-hole susceptibility of the minority species, where the mismatch of the Fermi surfaces of the two species plays an important role. We also propose an experimental protocol for detecting the p-wave superfluidity and discuss the corresponding experimental signatures.

8 pages, 6 figures

References in corpus (16)

• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Theory of ultracold Fermi gases
• Observation of the Pairing Gap in a Strongly Interacting Fermi Gas
• Itinerant Ferromagnetism in a Fermi Gas of Ultracold Atoms
• Superconductivity in the repulsive Hubbard model: an asymptotically exact weak-coupling solution
• Scattering Length Scaling Laws for Ultracold Three-Body Collisions
• Induced P-wave Superfluidity in Asymmetric Fermi Gases
• Renormalization Group Theory for the Imbalanced Fermi Gas
• Superconductivity from repulsive interactions in the two dimensional electron gas
• Mixtures of ultracold fermions with unequal masses
• Stable Fulde-Ferrell-Larkin-Ovchinnikov pairing states in 2D and 3D optical lattices
• Renormalization Group Approach to Strong-Coupled Superconductors
• Itinerant ferromagnetism in a two-dimensional atomic gas
• Induced P-wave superfluidity within full energy-momentum dependent Eliashberg approximation in asymmetric dilute Fermi gases
• Induced p-wave superfluidity in strongly interacting imbalanced Fermi gases
• Singlet and Triplet Superfluid Competition in a Mixture of Two-Component Fermi and One-Component Dipolar Bose Gases

Cited by in corpus (1)

• Excitation Spectra and Hard-core Thermodynamics of Bosonic Atoms In Double Well Optical Lattices