Perspectives for a reversible light-induced change in hydrogenated nanocrystalline silicon

The measurements in this report suggest that the Raman shift taking place in nanocrystalline silicon is based on the orientational disordering activated by the energy of the irradiating light. We estimate the orientational disordering of crystallites in nanocrystalline silicon in terms of a correlation length and the root mean square (rms) bond angle deviation. We propose that Raman shift determines the correlation length and the rms bond angle deviation, and ultimately indicates the degree of structural disordering in nanocrystalline silicon.