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arXiv · 0710.2259

Sub-THz electrodynamics of the graphene-like superconductor CaAlSi

S. Lupi·L. Baldassarre·M. Ortolani·C. Mirri·U. Schade·R. Sopracase·T. Tamegai·R. Fittipaldi·A. Vecchione·P. Calvani
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Abstract

We report the first optical study of CaAlSi, a superconductor which displays both the crystal structure of MgB2 and the electronic band structure of intercalated graphites. The reflectivity of a CaAlSi single crystal was measured down to sub-THz frequencies and to 3.3 K, with the use of Coherent Synchrotron Radiation. A superconducting gap in the hexagonal planes, two gaps along the c axis were found and measured, as expected from the structure of the CaAlSi Fermi surface. The anisotropic optical parameters of the normal state were also determined.

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S. Lupi, L. Baldassarre, M. Ortolani, C. Mirri, U. Schade, R. Sopracase, T. Tamegai, R. Fittipaldi, A. Vecchione, P. Calvani. 2007-10-11. Sub-THz electrodynamics of the graphene-like superconductor CaAlSi. https://doi.org/10.1103/physrevb.77.054510

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