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arXiv · cond-mat/9703042

The Ward identity and nonadiabatic corrections to the quasiparticle self-energy

O. V. Danylenko·O. V. Dolgov·V. V. Losyakov
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Abstract

In some newly discovered materials the ratio of phonon to electron energies is no longer small. We have investigated the basement of the recently proposed gauge-invariant self-consistent method and found conditions of its applicability.

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O. V. Danylenko, O. V. Dolgov, V. V. Losyakov. 1997-03-04. The Ward identity and nonadiabatic corrections to the quasiparticle self-energy. https://doi.org/10.1016/s0375-9601(97)00226-0

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