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Pairing in the Bogoliubov-de Gennes equations

Yong-Jihn Kim
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Abstract

It is shown that the Bogoliubov-de Gennes equations pair the electrons in states which are linear combinations of the normal states. Accordingly, the BCS-like reduction procedure is required to choose a correct pairing. For a homogeneous system, we point out that the kernel of the self-consistency equation derived from the Bogoliubov-de Gennes equations needs to be constrained by the BCS pairing condition. In the presence of ordinary impurities, on the other hand, the Bogoliubov-de Gennes equations should be supplemented by Anderson's pairing condition to obtain the correct vacuum state by the corresponding unitary transformation. This results in localization correction to the phonon-mediated interaction.

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Yong-Jihn Kim. 1997-01-15. Pairing in the Bogoliubov-de Gennes equations. https://doi.org/10.1142/s0217979297000885

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