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arXiv · 1710.06764

Friedel oscillations as an origin of Mahan exciton/Fermi edge singularity phenomena in optical spectra of degenerated semiconductors

V. V. Solovyev·I. V. Kukushkin
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Abstract

We point out at the possible relationship between the two many-body phenomena: Friedel oscillations and Mahan exciton/Fermi edge singularity in a recombination process of a localized valence band hole with a degenerate electron system. It is qualitatively described that the oscillating electron density around the screened potential of a neutral acceptor can modify the wavefunction of the valence band hole and thus promote its recombination with electrons near Fermi-surface. The role of a finite hole mass for the net balance of the two hole energies: the kinetic energy and Coulomb attraction to the degenerate electron system, - is discussed and explicitly shown to be crucial for the occurrence of Mahan enhancement phenomena.

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V. V. Solovyev, I. V. Kukushkin. 2017-10-18. Friedel oscillations as an origin of Mahan exciton/Fermi edge singularity phenomena in optical spectra of degenerated semiconductors. https://arxiv.org/abs/1710.06764

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