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arXiv · 0810.3565

Third order susceptibility: general formalism for photoinduced current density in semiconductors

M. Combescot·O. Betbeder-Matibet
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Abstract

This paper contains a detailed derivation of the photoinduced current density at third order in the coupling between a semiconductor and a multifrequency photon field, starting from its standard textbook expression as a third order time integral of a triple commutator. Due to a major intrinsic problem linked to this triple commutator, such a derivation has been made possible quite recently only, thanks to the tools developed in the composite-boson many-body theory we have just constructed. The photoinduced current density is shown to ultimately read in a compact form, in terms of the Pauli and Coulomb scatterings for exciton-exciton interactions introduced in this theory. Representation in Shiva diagrams is also given to better grasp the physics of the various contributions.

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M. Combescot, O. Betbeder-Matibet. 2008-10-29. Third order susceptibility: general formalism for photoinduced current density in semiconductors. https://arxiv.org/abs/0810.3565

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