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Field-angle Dependence of the Zero-Energy Density of States in the Unconventional Heavy-Fermion Superconductor CeCoIn5

H. Aoki·T. Sakakibara·H. Shishido·R. Settai·Y. Onuki·P. Miranovic·K. Machida
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Abstract

Field-angle dependent specific heat measurement has been done on the heavy-fermion superconductor CeCoIn5 down to ~ 0.29 K, in a magnetic field rotating in the tetragonal c-plane. A clear fourfold angular oscillation is observed in the specific heat with the minima (maxima) occurring along the [100] ([110]) directions. Oscillation persists down to low fields H << Hc2, thus directly proving the existence of gap nodes. The results indicate that the superconducting gap symmetry is most probably of dxy type.

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H. Aoki, T. Sakakibara, H. Shishido, R. Settai, Y. Onuki, P. Miranovic, K. Machida. 2003-11-30. Field-angle Dependence of the Zero-Energy Density of States in the Unconventional Heavy-Fermion Superconductor CeCoIn5. https://doi.org/10.1088/0953-8984%2F16%2F3%2Fl02

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