LINEAR-CHAIN-MODEL INTERPRETATION OF RESONANT RAMAN-SCATTERING IN GENSIM MICROSTRUCTURES

We use a linear-chain model with bond polarizabilities to simulate the Raman spectrum of a Ge5Si5 microstructure which presents interface ro ughness both in the atomic scale and in the form of terraces of latera l dimensions equal or superior to 10(2) Angstrom. The model is not ver y successful in reproducing the effects of the short range roughness, but simulates effectively the consequences of terracing on the Raman s pectrum of our sample. A detailed line shape analysis of one of these Raman lines leads to insights into the electronic states which are res ponsible for the resonant effects in the Raman cross section.