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arXiv · 1112.3609

Quantum limiting behaviors of a vortex core in an anisotropic gap superconductor

S. Kaneko·K. Matsuba·M. Hafiz·K. Yamasaki·E. Kakizaki·N. Nishida·H. Takeya·K. Hirata·T. Kawakami·T. Mizushima·K. Machida
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Abstract

Quantized bound states at a vortex core are discretized in YNi$_2$B$_2$C. By using scanning tunneling spectroscopy with an unprecedented 0.1 nm spatial resolution, we find and identify the localized spectral structure, where in addition to the first main peak with a positive low energy, a second subpeak coming from the fourfold symmetric gap structure is seen inside the energy gap. Those spectral features are understood by solving the Bogoliubov-de Gennes equation for a fully three-dimensional gap structure. A particle-hole asymmetric spectrum at the core site and quantum oscillation in the spectra are clearly observed.

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S. Kaneko, K. Matsuba, M. Hafiz, K. Yamasaki, E. Kakizaki, N. Nishida, H. Takeya, K. Hirata, T. Kawakami, T. Mizushima, K. Machida. 2012-06-11. Quantum limiting behaviors of a vortex core in an anisotropic gap superconductor. https://doi.org/10.1143/jpsj.81.063701

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