Anisotropy of electron-phonon coupling in single wurtzite CdS nanowires

Abstract

Orientation dependent electron phonon (EP) coupling on single wurtzite CdS nanowires with average diameter of 60 nm has been studied using polarized Raman spectroscopy. The Raman spectra of nanowires are compared with those of bulk ribbon. Different from the bulk sample, the EP coupling of the nanowires is polarized along the longitudinal axis of wire and the diametral coupling strength exhibits a minimum due to the finite size effect of the Fröhlich potential. These results show that the highly anisotropic geometry of CdS nanowires is a dominant factor in determining the anisotropy of EP coupling. © 2007 American Institute of Physics.