Rigorous asymptotic study of the screened electrostatic potential in a thin dielectric slab

Didier Felbacq; Emmanuel Rousseau

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arXiv · 1902.01066

Rigorous asymptotic study of the screened electrostatic potential in a thin dielectric slab

Didier Felbacq·Emmanuel Rousseau

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Abstract

The screened Coulomb potential plays a crucial role in the binding energies of excitons in a thin dielectric slab. The asymptotic behavior of this potential is studied when the thickness of the slab is very small as compared to the exciton Bohr radius. A regularized expression is given and the exact effective 2D potential is derived. These expressions may be useful for the computation of the exciton binding energy in 2D or quasi-2D materials.

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Didier Felbacq, Emmanuel Rousseau. 2019-02-04. Rigorous asymptotic study of the screened electrostatic potential in a thin dielectric slab. https://arxiv.org/abs/1902.01066

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