Isotope-disorder-induced line broadening of phonons in the raman spectra of SiC

The width of phonon lines in the Raman spectra of ideal isotopically purr s olids is determined by inelastic scattering processes. In solids that conta in a mixture of different isotopes of one atomic constituent, elastic scatt ering clue to isotopic mass disorder opens up decay channels that result in additional line broadening. We use different polytypes of SiC with an asso ciated number of Raman active modes in older to experimentally validate the proportionality between linewidth and phonon density of states predicted b y a simple elastic scattering theory.