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Search for E_2g phonon modes in MgB_2 single crystals by point-contact spectroscopy

Yu. G. Naidyuk·I. K. Yanson·O. E. Kvitnitskaya S. Lee·S. Tajima
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Abstract

The electron-phonon interaction in magnesium diboride MgB_2 single crystals is investigated by point-contact (PC) spectroscopy. For the first time the electron coupling with E_2g phonon modes is resolved in the PC spectra. The correlation between intensity of the extremely broad E_2g modes in the PC spectra and value of the superconducting gap is established. Our observations favor current theoretical models for electron-phonon mediated superconductivity in MgB_2 and they better match the harmonic phonons model.

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Yu. G. Naidyuk, I. K. Yanson, O. E. Kvitnitskaya S. Lee, S. Tajima. 2002-11-07. Search for E_2g phonon modes in MgB_2 single crystals by point-contact spectroscopy. https://doi.org/10.1103/physrevlett.90.197001

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