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arXiv · 2103.03322

Calculation of the nonlinear response functions of intra-exciton transitions in two-dimensional transition metal dichalcogenides

J. C. G. Henriques·Høgni C. Kamban·Thomas G. Pedersen·N. M. R. Peres
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Abstract

In this paper, we study the third-order nonlinear optical response due to transitions between excitonic levels in two-dimensional transition metal dichalcogeniedes. To accomplish this, we use methods not applied to the description of excitons in two-dimensional materials so far and combined with a variational approach to describe the $1s$ excitonic state. The aforementioned transitions allow to probe dark states which are not revealed in absorption experiments. We present general formulas capable of describing any third-order process. The specific case of two-photon absorption in WSe2 is studied. The case of the circular well is also studied as a benchmark of the theory.

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J. C. G. Henriques, Høgni C. Kamban, Thomas G. Pedersen, N. M. R. Peres. 2021-03-04. Calculation of the nonlinear response functions of intra-exciton transitions in two-dimensional transition metal dichalcogenides. https://doi.org/10.1103/physrevb.103.235412

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