Field dependence of the superconducting basal plane anisotropy of TmNi2B2C

TitleField dependence of the superconducting basal plane anisotropy of TmNi2B2C
Publication TypeJournal Article
Year of Publication2012
AuthorsDas P, Densmore JM, Rastovski C, Schlesinger KJ, Laver M, Dewhurst CD, Littrell K, Bud'ko SL, Canfield PC, Eskildsen MR
Journal TitlePhysical Review B
Date Published10
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberWOS:000309345400006
Keywordscore, LATTICE, magnetic-structure, single-crystal tmni2b2c, vortices

The superconductor TmNi2B2C possesses a significant fourfold basal plane anisotropy, leading to a square vortex lattice (VL) at intermediate fields. However, unlike other members of the borocarbide superconductors, the anisotropy in TmNi2B2C appears to decrease with increasing field, evident by a reentrance of the square VL phase. We have used small-angle neutron scattering measurements of the VL to study the field dependence of the anisotropy. Our results provide a direct, quantitative measurement of the decreasing anisotropy. We attribute this reduction of the basal plane anisotropy to the strong Pauli paramagnetic effects observed in TmNi2B2C and the resulting expansion of vortex cores near H-c2.

URL<Go to ISI>://WOS:000309345400006
Alternate JournalPhys. Rev. B