On the Raman scattering from semiconducting nanowires

Abstract

We present a short review of recent work on the unusual Raman scattering characteristics in semiconductor nanowires, focusing on the dependence of the intensity, spectral and spatial character of the scattering response on the size, shape and composition of the nanowires. Results of Raman scattering collected from individual Si and nanowires and nanocones indicate that the observed enhancement is dependent on the diameter (d), the excitation wavelength (λlaser) and the incident polarization state. Strong agreement between experimental data and model calculations of scattering from an infinite dielectric cylinder is found. This size dependence is in accordance with other recent findings in which a diameter-dependent dipolar 'antenna' pattern for the scattered intensity and a cross-sectional shape dependence of the surface optic (SO) phonon dispersions were seen. Further providing evidence of the nanowire shape and size dependence on Raman scattering, these results suggest manipulation of classical electromagnetic scattering signatures, thereby expanding opportunities for engineering the photonic and sensing properties of nanowires. Copyright © 2007 John Wiley & Sons, Ltd.