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Raman scattering from a superconductivity-induced bound state in $MgB_2$

R. Zeyher
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Abstract

It is shown that the sharp peak in the $E_{2g}$ Raman spectrum of superconducting $MgB_2$ is due to a bound state caused by the electron-phonon coupling. Our theory explains why this peak appears only in the spectra with $E_{2g}$ symmetry and only in the $σ$ but not $π$ bands. The properties of the bound state and the Raman spectrum are investigated, also in the presence of impurity scattering.

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R. Zeyher. 2003-02-11. Raman scattering from a superconductivity-induced bound state in $MgB_2$. https://doi.org/10.1103/physrevlett.90.107002

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