Stimulated Raman Scattering in Nanorod Silicon Carbide Films

When the film is excited by a very low excitation energy, the spontaneous Raman scattering emerges. The intensity of Raman scattering is proportional to the excitation power below the threshold excitation. When the excited power reaches the excitation threshold, the intensity of Stokes light strongly increases. Meanwhile an anti Stokes light at 495 nm and multiple order but small Stokes peaks occur. The intensity of Stokes light is much larger than that of anti Stokes. The full width of half maximum (FWHM) of Stokes peak is reduced from 0.4 nm to less than 0.2 nm, the scattering angle between both Stokes and incident lights becomes less than 1°, and the angle between the Stokes and anti Stokes lights is about 3°. When the exciting power is in excess of the threshold, anti Stokes and multiple Raman scattering peaks reappear. These experiments can be unlimitedly repeated. From this experiment, we can exclude the possibility of spontaneous Raman scattering. It is suggested that the nanorods are a quantum line dimension having a large surface. There will be Raman differential scattering section so long as the nanorod films become very strong scattering media; the surface enhanced Raman scattering will be produced, the nanorod films of SiC will form a strong multiple scattering resonance cavities so as to form the stimulated Raman scattering oscillation.

When the film is excited by a very low excitation energy, thespontaneous Raman scattering emerges. The intensity of Ramanscattering is proportional to the Excitation power below thethreshold excitation. When the excited power reaches the Excitationthreshold, the intensity of Stokes light strongly increases.Meanwhile an anti- Stokes light at 495 nm and multiple order butsmall Stokes peaks occur. The intensity of Stokes light is muchlarger than that of anti-Stokes.