Xray-Edge Spectra From Sea-Bosons-I

Girish S. Setlur

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arXiv · cond-mat/0111423

Xray-Edge Spectra From Sea-Bosons-I

Girish S. Setlur

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Abstract

The well-studied phenomenon of X-ray edge singularities is revisited using the sea-boson approach that has recently been placed on a rigorous footing. We are able to reproduce the well-known result namely, Mahan's power law divergences. Unlike the work of Schotte and Schotte, no linearization of the bare fermion dispersion is needed, which, by their own admission, is a source of some difficulty. Our approach also brings out some differences between the different dimensions which is not present in their work. Finally, our work also allows for easy generalization to potentials more realistic than the simple delta-function used commonly in the literature.

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Girish S. Setlur. 2001-11-22. Xray-Edge Spectra From Sea-Bosons-I. https://arxiv.org/abs/cond-mat/0111423

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