Phonon structure in point-contact spectra of MgB$_2$

I. K. Yanson

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arXiv · cond-mat/0405246

Phonon structure in point-contact spectra of MgB$_2$

I. K. Yanson

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Abstract

In strong-coupling superconductors with a short electron mean free path the self-energy effects in the superconducting order parameter play a major role in the phonon manifestation of the point-contact spectra at above-gap energies. We compare the expressions for the nonlinear conductivity of tunnel, ballistic, and diffusive point-contacts and show that these expression are similar and correspond to the measurements of the phonon structure in the point-contact spectra for the $π$-band of MgB$_{2}$.

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I. K. Yanson. 2004-05-12. Phonon structure in point-contact spectra of MgB$_2$. https://arxiv.org/abs/cond-mat/0405246

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