Temperature dependence of the upper critical field of an anisotropic singlet superconductivity in a square lattice tight-binding model in parallel magnetic fields

Abstract

Upper critical field parallel to the conducting layer is studied in anisotropic type-II superconductors on square lattices. We assume enough separation of the adjacent layers, for which the orbital pair-breaking effect is suppressed for exactly aligned parallel magnetic field. In particular, we examine the temperature dependence of the critical field H_c(T) of the superconductivity including the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO or LOFF) state, in which the Cooper pairs have non-zero center-of-mass momentum q. In the system with the cylindrically symmetric Fermi-surface, it is known that H_c(T) of the d-wave FFLO state exhibits a kink at a low temperature due to a change of the direction of q in contrast to observations in organic superconductors. It is shown that the kink disappears when the Fermi-surface is anisotropic to some extent, since the direction of q is locked in an optimum direction independent of the temperature.

5 pages, 5 figures, revtex.sty, submitted to J.Phys.Soc.Jpn

References in corpus (2)

• Influence of orbital pair breaking on paramagnetically limited states in clean superconductors
• Enhancement of the upper critical field and a field-induced superconductivity in antiferromagnetic conductors

Cited by in corpus (11)

• Phase Diagram and Spectroscopy of FFLO states of two-dimensional d-wave superconductors
• Fulde-Ferrell-Larkin-Ovchinnikov State and Field-Induced Superconductivity in an Organic Superconductor
• Crossover from the vortex state to the Fulde-Ferrell-Larkin-Ovchinnikov state in quasi-two-dimensional superconductors
• Different types of the Fulde-Ferrell-Larkin-Ovchinnikov states induced by anisotropy effects
• Thermodynamic evidence for the formation of a Fulde-Ferrell-Larkin-Ovchinnikov phase in the organic superconductor $\lambda$-(BETS)${}_2$GaCl${}_4$
• Dimensional Crossover of the Fulde-Ferrell-Larkin-Ovchinnikov State in Strongly Pauli-Limited Quasi-One-Dimensional Superconductors
• Fermi surface effect on spontaneous breaking of time-reversal symmetry in unconventional superconducting films
• Antiferromagnetic superconductors with effective mass anisotropy in magnetic fields
• Pairing competition in a quasi-one-dimensional model of organic superconductors (TMTSF)${}_{2}X$ in magnetic field
• Stabilization of the Fulde-Ferrell-Larkin-Ovchinnikov State by Tuning In-plane Magnetic-Field Direction: Application to a Quasi-One-Dimensional Organic Superconductor
• Fulde-Ferrell-Larkin-Ovchinnikov State in Perpendicular Magnetic Fields in Strongly Pauli-Limited Quasi-Two-Dimensional Superconductors