Strong Fulde-Ferrell Larkin-Ovchinnikov pairing fluctuations in polarized Fermi systems
Authors: Pini M.; Pieri P.; Calvanese Strinati G.
Autors Affiliation: School of Science and Technology, Physics Division, Universita di Camerino, (MC), Camerino, 62032, Italy; CNR-INO, Istituto Nazionale di Ottica, (FI), Sede di Sesto Fiorentino, 50019, Italy; Dipartimento di Fisica e Astronomia, Universita di Bologna, (BO), Bologna, 40127, Italy; INFN, Sezione di Bologna, (BO), Bologna, 40127, Italy; INFN, Sezione di Perugia, (PG), Perugia, 06123, Italy; CNR-INO, Istituto Nazionale di Ottica, Sede di Firenze (FI), Firenze, 50125, Italy
Abstract: We calculate the pair susceptibility of an attractive spin-polarized Fermi gas in the normal phase, as a function of the pair momentum. Close to unitarity, we find a strong enhancement of Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) pairing fluctuations over an extended region of the temperature-polarization phase diagram, which manifests itself as a pronounced peak in the pair-momentum distribution at a finite pair momentum. This peak should be amenable to experimental observation at achievable temperatures in a boxlike trapping potential, as a fingerprint of FFLO pairing. Our calculations rest on a self-consistent t-matrix approach which, for the unitary balanced Fermi gas, has been validated against experimental data for several thermodynamic quantities.
Journal/Review: PHYSICAL REVIEW RESEARCH
Volume: 3 (4) Pages from: 043068-1 to: 043068-10
More Information: Financial support from the Italian MIUR under Project PRIN2017 (20172H2SC4) is acknowledged.KeyWords: BCS superconductivity; density-wave; Bose-condensation; phase-diagram; transition; evolution; state; gasDOI: 10.1103/PhysRevResearch.3.043068