The optical properties of semiconductor nanowires (NWs) are object of study
because they are the building blocks of the future nanophotonic devices. The
high refractive index and its reduced dimension, make them suitable for
photon engineering. The study of the interaction between NWs and visible
light has revealed resonances of the light absorption/scattering by the NWs.
Micro-Raman spectroscopy is used as a characterization method of semiconductor
NWs. The relation between the Raman intensity and the incident
electromagnetic (EM) field permits to study the light/NW interaction through
the micro-Raman spectra of individual NWs. As compared to either metallic
or dielectric NWs, the semiconductor NWs add additional tools to modify its
interaction with light, for example, the composition, the presence of
heterostructures, both axial and radial, doping, and the surface morphology.
One presents herein a study of the optical response of group IV semiconductor
NWs to visible photons. The study is experimentally carried out through the micro-Raman spectroscopy of different group IV NWs, both homogeneous and heterostructured (SiGe/Si), and the results are analyzed in terms of the EM modeling of the light/NW interaction using finite element methods (FEMs). The heterostructures are seen to produce additional resonances allowing new photonic capacities to the semiconductor NWs.
