Mode-controlled random laser assisted by stimulated Raman scattering

Abstract In this study, a reproducible and stable mode random laser is fabricated from Rhodamine 6G dye-containing ZnO@C-N microstructures by using an approach based on the coupling of the stimulated Raman scattering effect and random lasing process. Under intense pump energy, the Raman peaks of Rhodamine 6G work as seeds, and multiple elastic scattering in the disordered medium will amplify them. On the other hand, ZnO@C-N porous microstructures with plenty of nanosheets and high surface area effectively act as scatterer centers in providing strong multiple elastic scattering. So that, the strong feedback from nanosheets of the individual microstructures, allows the system to operate at a low concentration of scatterers (as low as 2mg/ml). Moreover, the enhancement of Raman modes as a function of the pump pulse energies and scatterers concentrations is examined. The results show that the Raman modes after manifestation are stable and reproduce well from pulse-to-pulse pump energy variation. Our findings introduce a new approach to tune the wavelength of random lasers for real applications and also enable the laser mode selection.