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arXiv · 0706.1863

Positions of Point-Nodes in Borocarbide Superconductor YNi2B2C

Yuki Nagai·Yusuke Kato·Nobuhiko Hayashi·Kunihiko Yamauchi·Hisatomo Harima
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Abstract

To determine the superconducting gap function of YNi2B2C, we calculate the local density of states (LDOS) around a single vortex core with the use of Eilenberger theory and the band structure calculated by local density approximation assuming various gap structures with point-nodes at different positions. We also calculate the angular-dependent heat capacity in the vortex state on the basis of the Doppler-Shift method. Comparing our results with the STM/STS experiment, the angular-dependent heat capacity and thermal conductivity, we propose the gap-structure of YNi2B2C, which has the point-nodes and gap minima along <110>. Our gap-structure is consistent with all results of angular-resolved experiments.

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Yuki Nagai, Yusuke Kato, Nobuhiko Hayashi, Kunihiko Yamauchi, Hisatomo Harima. 2007-06-13. Positions of Point-Nodes in Borocarbide Superconductor YNi2B2C. https://doi.org/10.1103/physrevb.76.214514

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