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Electron diffusivities in MgB2 from point contact spectroscopy

Y. Bugoslavsky·Y. Miyoshi·G. K. Perkins·A. D. Caplin·L. F. Cohen·A. V. Pogrebnyakov·X. X. Xi
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Abstract

We demonstrate that the variation of the Andreev reflection with applied magnetic field provides a direct means of comparing the properties of MgB2 with the theory for a dirty two-band superconductor, and we find good agreement between the two. The ratio of electron diffusivities in the s and p bands can be inferred from this experiment. We find that the field dependence of the density of states at the Fermi level in the p band is independent of the field direction, and that the anisotropic upper critical field is determined by the anisotropic diffusivity in the s band.

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Y. Bugoslavsky, Y. Miyoshi, G. K. Perkins, A. D. Caplin, L. F. Cohen, A. V. Pogrebnyakov, X. X. Xi. 2005-02-05. Electron diffusivities in MgB2 from point contact spectroscopy. https://doi.org/10.1103/physrevb.72.224506

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