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arXiv · 2105.10734

Non-Degenerate Two-Photon Absorption in ZnSe: Experiment and Theory

L. Krauss-Kodytek·W. -R. Hannes·T. Meier·C. Ruppert·M. Betz
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Abstract

We experimentally and theoretically investigate the non-degenerate two-photon absorption coefficient $β(ω_1,ω_2)$ in the prototypical semiconductor ZnSe. In particular, we provide a comprehensive data set on the dependence of $β(ω_1,ω_2)$ on the non-degeneracy parameter $ω_1/ω_2$ with the total frequency sum $ω_1+ω_2$ kept constant. We find a substantial increase of the two-photon absorption strength with increasing $ω_1/ω_2$. In addition, different crystallographic orientations and polarization configurations are investigated. The nonlinear optical response is analyzed theoretically by evaluating the multiband semiconductor Bloch equations including inter- and intraband excitations in the length gauge. The band structure and the matrix elements are taken an eight-band k.p model. The simulation results are in very good agreement with the experiment.

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L. Krauss-Kodytek, W. -R. Hannes, T. Meier, C. Ruppert, M. Betz. 2021-08-11. Non-Degenerate Two-Photon Absorption in ZnSe: Experiment and Theory. https://doi.org/10.1103/physrevb.104.085201

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