Fabrication of a random laser gain medium using Rhodamine 101 dye doped with SiO2 nanoparticles by Sol-Gel technique

•Our study focuses on the intriguing field of random lasers, particularly the fabrication of their gain mediums using a sol-gel technique and pumping with a blue nano-second pulsed laser at 473 nm to achieve a narrower peak.•We employed a sol–gel approach to prepare solid gain mediums consisting of Rhodamine 101 (R640) dye at different concentrations with SiO2 nanoparticles (NPs) and pump these solid gain media with a pulsed blue laser operating at a wavelength of 473 nm.•As the pumping power increases, the scattering mean free path decreases, which leads to a lower lasing threshold. The pumping process resulting in the generation of coherent and directional emission at 532–536 nm with a remarkably narrow linewidth of less than 4 nm in all samples. Random laser gain media are demonstrated by different concentrations of Rhodamine 101 dye solution mixed with SiO2 nanoparticles. For this purpose, these mediums are fabricated using the sol–gel technique and supplied with a pulsed blue laser to produce random lasing, while the light that reflects is collected using a spectrometer. Fluorescence and lasing activity were amplified as a consequence of nanoparticle scattering due to this optical pumping process. The results demonstrate coherent random lasing at 532–536 nm with the best FWHM equal to 2.1 nm at the optimal concentration (1 × 10−4 M).