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arXiv · 2308.09188

Non-Hermitian dispersion sign reversal of radiative resonances in two dimensions

R. Binder·J. S. Schaibley·N. H. Kwong
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Abstract

In a recent publication [Wurdack et al., Nat. Comm. 14:1026 (2023)], it was shown that in microcavities containing atomically thin semiconductors non-Hermitian quantum mechanics can lead to negative exciton polariton masses. We show that mass-sign reversal can occur generally in radiative resonances in two dimensions (without cavity) and derive conditions for it (critical dephasing threshold etc.). In monolayer transition-metal dichalcogenides, this phenomenon is not invalidated by the strong electron-hole exchange interaction, which is known to make the exciton massless.

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R. Binder, J. S. Schaibley, N. H. Kwong. 2023-08-17. Non-Hermitian dispersion sign reversal of radiative resonances in two dimensions. https://arxiv.org/abs/2308.09188

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