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arXiv · 1408.3981

Three-particle Complexes in Two-Dimensional Semiconductors

Bogdan Ganchev·Neil Drummond·Igor Aleiner·Vladimir Fal'ko
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Abstract

We map the three-body problem in two dimensions onto one particle in a three dimensional potential treatable by a purposely-developed boundary-matching-matrix method. We evaluate binding energies of trions $X^{\pm}$, excitons bound by a donor/acceptor charge $X^{D/A}$, and overcharged acceptors/donors in two-dimensional atomic crystals of transition metal dichalcogenides, where interaction between charges features logarithmic behavior at intermediate distances. We find that dissociation energy of $X^{\pm}$ is, typically, much larger than that of localised exciton complexes, so that trions are more resilient to heating, despite that their recombination line in optics is much less red-shifted from the exciton line, as compared to $X^{D/A}$

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Bogdan Ganchev, Neil Drummond, Igor Aleiner, Vladimir Fal'ko. 2015-03-12. Three-particle Complexes in Two-Dimensional Semiconductors. https://doi.org/10.1103/physrevlett.114.107401

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