Field dependence of the superconducting basal plane anisotropy of TmNi₂B₂C

TY - JOUR

T1 - Field dependence of the superconducting basal plane anisotropy of TmNi2B2C

AU - Das, P.

AU - Densmore, J.M.

AU - Rastovski, C.

AU - Schlesinger, K.J.

AU - Laver, Mark

PY - 2012/10/1

Y1 - 2012/10/1

N2 - The superconductor TmNi 2B 2C 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 TmNi 2B 2C 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 TmNi 2B 2C and the resulting expansion of vortex cores near H c2.

AB - The superconductor TmNi 2B 2C 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 TmNi 2B 2C 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 TmNi 2B 2C and the resulting expansion of vortex cores near H c2.

U2 - 10.1103/PhysRevB.86.144501

DO - 10.1103/PhysRevB.86.144501

M3 - Journal article

SN - 2469-9950

VL - 86

SP - 144501

JO - Physical Review B

JF - Physical Review B

IS - 14

ER -