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arXiv · 1605.07916

Design of nonlinear optical response of multipole-type excitons by film thickness and incident pulse width

Takashi Kinoshita·Hajime Ishihara
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Abstract

We theoretically investigate the nonlinear optical pulse responses of excitons in a thin film where the excitonic center-of-mass motion is confined. A large interaction volume between excitons and radiation yields particular coupled states with radiative decay times reaching several femto-seconds. By considering two polarization directions of light, we reveal that these fast-decay modes dominantly survive in an optical Kerr spectra even under a massive nonradiative damping $Γ=30$ meV. The results clearly show that there is an optimal combination of the incident pulse width and the film thickness for maximizing the integrated intensity of nonlinear signals.

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Takashi Kinoshita, Hajime Ishihara. 2016-12-19. Design of nonlinear optical response of multipole-type excitons by film thickness and incident pulse width. https://doi.org/10.1103/physrevb.95.155418

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