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arXiv · 0804.2581

Enhancement of optical switching parameter and third-order optical nonlinearities in embedded Si nanocrystals: a theoretical assessment

Hasan Yıldırım·Ceyhun Bulutay
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Abstract

Third-order bound-charge electronic nonlinearities of Si nanocrystals (NCs) embedded in a wide band-gap matrix representing silica are theoretically studied using an atomistic pseudopotential approach. Nonlinear refractive index, two-photon absorption and optical switching parameter are examined from small clusters to NCs up to a size of 3 nm. Compared to bulk values, Si NCs show higher third-order optical nonlinearities and much wider two-photon absorption threshold which gives rise to enhancement in the optical switching parameter.

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Hasan Yıldırım, Ceyhun Bulutay. 2008-04-16. Enhancement of optical switching parameter and third-order optical nonlinearities in embedded Si nanocrystals: a theoretical assessment. https://doi.org/10.1016/j.optcom.2008.04.042

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