Fermi Surface Structure and Isotropic Stability of Fulde-Ferrell-Larkin-Ovchinnikov Phase in Layered Organic Superconductor β″-(BEDT-TTF)2SF5CH2CF2SO3

Crystals

Yasuhiro Nakazawa¹  Hiroki Akutsu¹  Shiori Sugiura²  Shinya Uji³  Taichi Terashima³  John A. Schlueter⁴  Syuma Yasuzuka⁵ 

[1] Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan;Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan;Institute for Materials Science, Tsukuba 305-0003, Japan;Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA;Research Center for Condensed Matter Physics, Hiroshima Institute of Technology, Hiroshima 731-5193, Japan;

关键词: organic superconductor;    resistance;    FFLO phase;    vortex dynamics;   

DOI  :  10.3390/cryst11121525

来源: DOAJ

【 摘 要 】

The Fermi surface structure of a layered organic superconductor $\beta$${}^{″}$-(BEDT-TTF)${}_2$SF${}_5$CH${}_2$CF${}_2$SO${}_3$ was determined by angular-dependent magnetoresistance oscillations measurements and band-structure calculations. This salt was found to have two small pockets with the same area: a deformed square hole pocket and an elliptic electron pocket. Characteristic corrugations in the field dependence of the interlayer resistance in the superconducting phase were observed at any in-plane field directions. The features were ascribed to the commensurability (CM) effect between the Josephson vortex lattice and the periodic nodal structure of the superconducting gap in the Fulde–Ferrell–Larkin–Ovchinnikov (FFLO) phase. The CM effect was observed in a similar field region for various in-plane field directions, in spite of the anisotropic nature of the Fermi surface. The results clearly showed that the FFLO phase stability is insensitive to the in-plane field directions.

【 授权许可】

Unknown