Random lasing emission from colloidal solutions of graphitic carbon nitride microstructures

Abstract

In this paper, we report on random lasing emission from colloidal solutions of graphitic carbon nitride (g-C3N4) microstructures. The g-C3N4 microstructures are dispersed in rhodamine B (RhB) dye solution to provide the necessary optical feedback via light multi-scattering events. RhB molecules provide optical gain via stimulated emission process under intense optical pumping. It is experimentally demonstrated that random lasing action occurs in the colloidal solution composed of dye and g-C3N4 microstructures, after a specific threshold. We study the pump dependent behavior of the proposed system. Since only amplified spontaneous emission is achieved from the solution of RhB dye without g-C3N4 microstructures, it is demonstrated that the existence of g-C3N4 microstructures has a key role in the observation of random lasing emission. Finally, we change the concentration of g-C3N4 microstructures and observe that the output intensity increases and the lasing threshold decreases by increasing the concentration of g-C3N4 microstructures. It is then verified that g-C3N4 microstructures can be a good candidate for the scattering medium in random lasers and the essential optical feedback for realizing random lasing emission is provided by light multi-scattering from g-C3N4 microstructures.