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arXiv · 0706.3270

Theory of Fulde-Ferrell-Larkin-Ovchinnikov state of superconductors with and without inversion symmetry: Hubbard model approach

Takehito Yokoyama·Seiichiro Onari·Yukio Tanaka
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Abstract

We study Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state of superconductors with and without inversion symmetry based on the Hubbard model on the square lattice near half-filling, using the random phase approximation. We show that center of mass momentum $Q$ tends to be parallel to $x$- or y-axis in the presence of inversion symmetry, while $Q$ vector is likely to be perpendicular to the magnetic field in the absence of inversion symmetry. We also clarify that $d+f$-wave pairing is favored and the hetero spin triplet $f$-wave state is present in the FFLO state unlike state in the superconductors only with the Rashba type spin-orbit coupling (RSOC) originating from the broken inversion symmetry. The triplet $f$-wave state is enhanced by magnetic field and the RSOC. This stems from the reduction of the spin susceptibilities by the magnetic field and the RSOC.

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Takehito Yokoyama, Seiichiro Onari, Yukio Tanaka. 2007-06-22. Theory of Fulde-Ferrell-Larkin-Ovchinnikov state of superconductors with and without inversion symmetry: Hubbard model approach. https://doi.org/10.1143/jpsj.77.064711

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