Steady-state nonlinear optical response of excitons in monolayer MoSe$_2$

Muhed S. Rana; Joshua R. Hendrickson; Christopher E. Stevens; Michael R. Koehler; David G. Mandrus; Takashi Taniguchi; Kenji Watanabe; Nai H. Kwong; Rolf Binder; John R. Schaibley

arXiv · 2109.12160

Steady-state nonlinear optical response of excitons in monolayer MoSe$_2$

Muhed S. Rana·Joshua R. Hendrickson·Christopher E. Stevens·Michael R. Koehler·David G. Mandrus·Takashi Taniguchi·Kenji Watanabe·Nai H. Kwong·Rolf Binder·John R. Schaibley

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Abstract

Monolayer transition metal dichalcogenide (TMD) semiconductors such as MoSe$_2$ host strongly bound excitons which are known to exhibit a strong resonant third-order nonlinear response. Although there have been numerous studies of the ultrafast nonlinear response of monolayer TMDs, a study of the steady-state nonlinear response is lacking. We report a comprehensive study of the steady-state two-color nonlinear response of excitons in hBN-encapsulated monolayer MoSe$_2$ at 7 K. We observe differential transmission (DT) signals associated with the neutral and charged exciton species, which is strongly dependent on the polarization of the pump and probe. Our results are compared to a theoretical model based on a T-matrix formulation for exciton-exciton, exciton-trion, and trion-trion correlations. The parameters are chosen such that the theory accurately reproduces the experimental DT spectrum, which is found to be dominated by two-exciton correlations without strong biexciton binding, exciton-trion attractive interactions, and strong spin mixing through incoherent relaxation.

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Muhed S. Rana, Joshua R. Hendrickson, Christopher E. Stevens, Michael R. Koehler, David G. Mandrus, Takashi Taniguchi, Kenji Watanabe, Nai H. Kwong, Rolf Binder, John R. Schaibley. 2021-09-24. Steady-state nonlinear optical response of excitons in monolayer MoSe$_2$. https://arxiv.org/abs/2109.12160

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