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Point-contact spectroscopy of two-band superconductor MgB2

I. K. Yanson·Yu. G. Naidyuk
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Abstract

The progress in investigation of two-band superconductor MgB$_2$ by the point-contact spectroscopy (PCS) is given. Results of study of superconducting gap temperature and magnetic field dependence for two-dimensional $σ$ and three-dimensional $π$ band and electron-phonon-interaction spectral function are presented. Correlation between the gap value and the intensity of the high T$_c$ driving force -- $E_{2g}$ boron vibration mode, is provided. PCS data on some nonsuperconducting transition metal diborides are surveyed for comparison.

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I. K. Yanson, Yu. G. Naidyuk. 2003-09-30. Point-contact spectroscopy of two-band superconductor MgB2. https://arxiv.org/abs/cond-mat/0309693

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