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Symmetry and Temperature dependence of the Order parameter in MgB2 from point contact measurements

A. Kohen·G. Deutscher
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Abstract

We have performed differential conductance versus voltage measurements of Au/MgB2 point contacts. We find that the dominant component in the conductance is due to Andreev reflection. The results are fitted to the theoretical model of BTK for an s-wave symmetry from which we extract the value of the order parameter (Delta) and its temperature dependence. From our results we also obtain a lower experimental bound on the Fermi velocity in MgB2.

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A. Kohen, G. Deutscher. 2001-03-25. Symmetry and Temperature dependence of the Order parameter in MgB2 from point contact measurements. https://doi.org/10.1103/physrevb.64.060506

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