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Optical measurements of the superconducting gap in MgB2

B. Gorshunov·C. A. Kuntscher·P. Haas·M. Dressel·F. P. Mena·A. B. Kuz'menko·D. van der Marel·T. Muranaka·J. Akimitsu
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Abstract

Far-infrared reflectivity studies on the polycrystalline intermetallic compound MgB_2 with a superconducting transition temperature T_c=39 K were performed at temperatures 20 K to 300 K. We observe a significant raise of the superconducting-to-normal state reflectivity ratio below 70 cm^{-1}, with a maximum at about 25-30 cm^{-1}, which gives a lower estimate of the superconducting gap of 2Δ(0)\approx3-4 meV.

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B. Gorshunov, C. A. Kuntscher, P. Haas, M. Dressel, F. P. Mena, A. B. Kuz'menko, D. van der Marel, T. Muranaka, J. Akimitsu. 2001-04-26. Optical measurements of the superconducting gap in MgB2. https://doi.org/10.1007/s100510170191

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