Red Random Laser Based on Thermocavitation : Synthesis and Characterization

In this work, we studied thermal blooming phenomena using a CW laser with a wavelength of 405 nm and an optical power of 100 mW focused on a quartz cuvette containing dye solution with different types of nanoparticles to generate thermocavitation. We observed that self-phase modulation (SPM) typical far-field loops suddenly shifted into a completely different diffraction pattern when the dye solution was heated beyond the self-phase modulation (SPM) using a focused laser beam. After SPM, this process, known as thermal blooming (TB), can be considered the next phase. In addition, we observed the effect of (Ag NWs, Fe₂O₃, and AgNWs: Fe₂O₃) NPs on the speed of bubble formation and their number. also observed random laser actions in both the presence and absence of thermal cavitation. The presence of a thermal cavity was found to have a significant impact on the pump threshold, spectral linewidth, and intensity of emission spectra.