FFLO states and quantum oscillations in mesoscopic superconductors and superfluid ultracold Fermi gases

Abstract

We have studied the distinctive features of the Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) instability and phase transitions in two--dimensional (2D) mesoscopic superconductors placed in magnetic field of arbitrary orientation and rotating superfluid Fermi gases with imbalanced state populations. Using a generalized version of the phenomenological Ginzburg-Landau theory we have shown that the FFLO states are strongly modified by the effect of the trapping potential confining the condensate. The phenomenon of the inhomogeneous state formation is determined by the interplay of three length scales: (i) length scale of the FFLO instability; (ii) 2D system size; (iii) length scale associated with the orbital effect caused either by the Fermi condensate rotation or magnetic field component applied perpendicular to the superconducting disc. We have studied this interplay and resulting quantum oscillation effects in both superconducting and superfluid finite -- size systems with FFLO instability and described the hallmarks of the FFLO phenomenon in a restricted geometry. The finite size of the system is shown to affect strongly the conditions of the observability of switching between the states with different vorticities.

11 pages, 5 figures, Submitted to PRA

References in corpus (4)

• Vortices and Superfluidity in a Strongly Interacting Fermi Gas
• Fulde-Ferrell-Larkin-Ovchinnikov State in Heavy Fermion Superconductors
• Aharonov-Bohm effect in superconducting LOFF state
• Multiple-quantized vortices in rotating LOFF state of ultracold Fermi superfluid gas

Cited by in corpus (11)

• The Fulde-Ferrell-Larkin-Ovchinnikov state for ultracold fermions in lattice and harmonic potentials: a review
• Cooling and thermometry of atomic Fermi gases
• Spectroscopy of the soliton lattice formation in quasi-one-dimensional fermionic superfluids with population imbalance
• Fermi-to-Bose crossover in a trapped quasi-2D gas of fermionic atoms
• Surface pair-density-wave superconducting and superfluid states
• Rotating Fulde-Ferrell-Larkin-Ovchinnikov state in cold Fermi gases
• Dimensional Crossover in a Spin-imbalanced Fermi gas
• Fulde-Ferrell-Larkin-Ovchinnikov superconductors near a surface
• Fulde-Ferrell-Larkin-Ovchinnikov state in strongly correlated d-wave superconductors
• Paramagnetic Meissner, vortex and 'onion' ground states in Fulde-Ferrell finite-size superconductor
• Extension of the Ginzburg - Landau approach for ultracold Fermi gases below a critical temperature