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Three-Body Collective Excitations in the Superconducting Phase of $MgB_2$

Naoum Karchev
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Abstract

It is shown that coherent behavior of Cooper's pairs and electrons in the two-band superconductors $MgB_2$ is possible as a result of a strong two-phonon-electron coupling. The spin-$\frac 12$ triples with zero angular momentum are made up of three spin-$\frac 12$ fermions with charge $\emph{e}$. They are gapped Fermi excitations with gap induced by the gaps of the single fermions. Their contribution to the thermodynamics of the $MgB_2$ superconductors is considered.

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Naoum Karchev. 2005-07-12. Three-Body Collective Excitations in the Superconducting Phase of $MgB_2$. https://doi.org/10.1088/0953-8984%2F18%2F5%2F007

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