Anomalous energy shift of laterally confined two-dimensional excitons

Shota Ono; Tomohiro Ogura

doi:10.1063/1.5040524

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arXiv · 1801.06923

Anomalous energy shift of laterally confined two-dimensional excitons

Shota Ono·Tomohiro Ogura

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Abstract

We theoretically investigate the energy of the ground state exciton confined to two-dimensional (2D) monolayers with circular shape. Within an effective mass approach employing a nonlocal screening effect on the Coulomb potential energy, we demonstrate how the exciton energy is correlated with the radius of the circle, electron-hole reduced mass, and 2D susceptibility. In addition, we show that a dead layer around the circle edge, into which the electron-hole pair cannot penetrate, is necessary for understanding the energy shift recently observed in monolayer WSe2 quantum dots.

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Shota Ono, Tomohiro Ogura. 2018-07-17. Anomalous energy shift of laterally confined two-dimensional excitons. https://doi.org/10.1063/1.5040524

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