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Thermal properties of MgB2: the effect of disorder on gap amplitudes and relaxation times of p and s bands

M. Putti·E. Galleani·I. Pallecchi·C. Bernini·P. Manfrinetti·A. Palenzona·M. Affronte
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Abstract

We present thermal conductivity and specific heat measurements on MgB2 and Mg-AlB2 samples. Thermal properties have been analysed by using a two-gap model in order to estimate the gap amplitudes, D(0)p and D(0)s and the intra-band scattering rates, Gss and Gpp. As a function of Al doping and disorder D(0)s rapidly decreases, while D(0)p is rather constant. Gss and Gpp are increased by the disorder, being Gpp more affected than Gss.

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M. Putti, E. Galleani, I. Pallecchi, C. Bernini, P. Manfrinetti, A. Palenzona, M. Affronte. 2003-06-05. Thermal properties of MgB2: the effect of disorder on gap amplitudes and relaxation times of p and s bands. https://doi.org/10.1016/j.physc.2004.02.171

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