Anisotropic s-wave superconductivity in borocarbides LuNi2B2C and YNi2B2C
Anisotropic s-wave superconductivity in borocarbides LuNi2B2C and YNi2B2C
复制标题
硼碳化物 LuNi2B2C 和 YNi2B2C 中的各向异性横波超导
DOI：
10.1103/physrevb.65.140502
复制
发表时间：
2001
影响因子：
3.7
通讯作者：
H. Won
中科院分区：
文献类型：
--
作者：
K. Maki;P. Thalmeier;H. Won
The symmetry of superconductivity in borocarbides ${\mathrm{LuNi}}_{2}{\mathrm{B}}_{2}\mathrm{C}$ and ${\mathrm{YNi}}_{2}{\mathrm{B}}_{2}\mathrm{C}$ is an outstanding issue. Here an anisotropic s-wave order parameter (or $s+g$ model) is proposed for ${\mathrm{LuNi}}_{2}{\mathrm{B}}_{2}\mathrm{C}$ and ${\mathrm{YNi}}_{2}{\mathrm{B}}_{2}\mathrm{C}.$ In spite of a substantial s-wave component, the present superconducting order parameter $\ensuremath{\Delta}(\mathbf{k})$ has nodes and gives rise to the $\sqrt{H}$ dependent specific heat in the vortex state (the Volovik effect). This model predicts the fourfold symmetry both in the angular dependent thermal conductivity and in the excess Dingle temperature in the vortex state, which should be readily accessible experimentally.
The symmetry of superconductivity in borocarbides ${\mathrm{LuNi}}_{2}{\mathrm{B}}_{2}\mathrm{C}$ and ${\mathrm{YNi}}_{2}{\mathrm{B}}_{2}\mathrm{C}$ is an outstanding issue. Here an anisotropic s-wave order parameter (or $s+g$ model) is proposed for ${\mathrm{LuNi}}_{2}{\mathrm{B}}_{2}\mathrm{C}$ and ${\mathrm{YNi}}_{2}{\mathrm{B}}_{2}\mathrm{C}.$ In spite of a substantial s-wave component, the present superconducting order parameter $\ensuremath{\Delta}(\mathbf{k})$ has nodes and gives rise to the $\sqrt{H}$ dependent specific heat in the vortex state (the Volovik effect). This model predicts the fourfold symmetry both in the angular dependent thermal conductivity and in the excess Dingle temperature in the vortex state, which should be readily accessible experimentally.