Microcrystal diamond powders as promising objects for the generation of multifrequency stimulated Raman scattering

The laws of Raman scattering in microcrystalline diamond powders are investigated depending on the size of diamond microresonators in the range of 1–600 mkm. The observed effect of the anomalously high intensity of spontaneous Raman scattering in diamond microresonators is explained by the “trapping” of electromagnetic radiation in them, the wavelength of which is smaller than the size of diamond microcrystals. Due to the “trapping” of photons in diamond microresonators, the density of electromagnetic energy for excitation and secondary radiation increases. The high quality factor of the fundamental optical mode in the vibrational spectrum of diamond and the anomalous increase in the intensity of Raman scattering in diamond microresonators open up possibilities for observing low-threshold stimulated multifrequency Raman scattering in microcrystalline diamond powders. The use of the generation lines of a pulsed solid-state YAG: Nd$^{3+}$ laser ($\lambda$ = 1064 nm) and its optical harmonics ($\lambda$ = 1064, 532, 354, 266 nm) as exciting radiation makes it possible to create a line of laser-frequency oscillators from the ultraviolet region that are equidistant in frequency shift to the terahertz range, promising for the study of biological and medical objects.