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arXiv · 1711.10513

Optical nonlinearities of excitons in monolayer MoS2

Daniel B. S. Soh·Christopher Rogers·Dodd J. Gray·Eric Chatterjee·Hideo Mabuchi
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Abstract

We calculate linear and nonlinear optical susceptibilities arising from the excitonic states of mono- layer MoS2 for in-plane light polarizations, using second-quantized bound and unbound exciton operators. Optical selection rules are critical for obtaining the susceptibilities. We derive the valley-chirality rule for the second harmonic generation in monolayer MoS2, and find that the third- harmonic process is efficient only for linearly polarized input light while the third-order two photon process (optical Kerr effect) is efficient for circularly polarized light using a higher order exciton state. The absence of linear absorption due to the band gap and the unusually strong two-photon third-order nonlinearity make the monolayer MoS2 excitonic structure a promising resource for coherent nonlinear photonics.

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Daniel B. S. Soh, Christopher Rogers, Dodd J. Gray, Eric Chatterjee, Hideo Mabuchi. 2018-03-28. Optical nonlinearities of excitons in monolayer MoS2. https://doi.org/10.1103/physrevb.97.165111

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