Abstract
A large amount of experimental and theoretical work in the past has convincingly shown that the binary compound MgB2 is a two gap superconductor (Liu et al., 2001; Golubov et al., 2002; Choi et al., 2002; Dahm, 2005). The two significantly different gaps exist on disconnected parts of the Fermi surface: a small gap (~2 meV) on the π bands and a large gap (~7 meV) residing on the σ bands. This leads to a number of peculiar consequences both in its magnetic properties and its microwave properties.
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Dahm, T. (2007). II.1 Magnesium diboride and the two-band scenario. In: Scharnberg, K., Kruchinin, S. (eds) Electron Correlation in New Materials and Nanosystems. NATO Science Series, vol 241. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-5659-8_8
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DOI: https://doi.org/10.1007/978-1-4020-5659-8_8
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