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arXiv · 1305.4278

Excitonic Collapse in Semiconducting Transition Metal Dichalcogenides

A. S. Rodin·A. H. Castro Neto
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Abstract

Semiconducting transition metal dichalcogenides (STMDC) are two-dimensional (2D) crystals characterized by electron volt size band gaps, spin-orbit coupling (SOC), and d-orbital character of its valence and conduction bands. We show that these materials carry unique exciton quasiparticles (electron-hole bound states) with energy within the gap but which can ``collapse'' in the strong coupling regime by merging into the band structure continuum. The exciton collapse seems to be a generic effect in these 2D crystals.

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A. S. Rodin, A. H. Castro Neto. 2013-11-12. Excitonic Collapse in Semiconducting Transition Metal Dichalcogenides. https://doi.org/10.1103/physrevb.88.195437

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