Bound electronic and free carrier nonlinearities in Silicon nanocrystals at 1550nm.

Abstract

We present a detailed investigation of the different processes responsible for the optical nonlinearities of silicon nanocrystals at 1550 nm. Through z-scan measurements, the bound-electronic and excited carrier contributions to the nonlinear refraction were measured in presence of two-photon absorption. A study of the nonlinear response at different excitation powers has permitted to determine the change in the refractive index per unit of photo-excited carrier density sigma(r) and the value of the real bound-electronic nonlinear refraction n(2be) as a function of the nanocrystals size. Moreover at high excitation power, a saturation of the nonlinear absorption was observed due to band-filling effects.

Cite this paper

@article{Span2009BoundEA, title={Bound electronic and free carrier nonlinearities in Silicon nanocrystals at 1550nm.}, author={Roberta Span{\`o} and Nicola Daldosso and Matteo Cazzanelli and Luigi Ferraioli and Luca Tartara and Junjua Yu and Vittorio Degiorgio and E Giordana and Jean Marc F{\'e}d{\'e}li and Lorenzo Pavesi}, journal={Optics express}, year={2009}, volume={17 5}, pages={3941-50} }