Correlating scatterer concentration and intensity threshold of random laser in niobium oxide particle colloids with dye solution

Abstract

Our study examines how the concentration of scatterers affects the intensity threshold of random laser (RL) action in colloids made of niobium oxide particles and Rhodamine B dye. This is the first reported instance of RL action in niobium oxide. We kept the dye (gain medium) concentration constant and quantified how varying concentrations of niobium oxide particles (scatterers) affect the RL intensity threshold. Our findings indicate an inverse relationship between the concentration of niobium oxide particles and the RL threshold. Increasing the niobium oxide concentration from 0.32 mM to 2.50 mM decreased the RL threshold by up to 70 %, suggesting that higher scatterer densities lead to enhanced efficiency of the lasing process. We noticed that the RL intensity thresholds decrease concerning scatterer concentration, highlighting the significant impact of scatterer density on lasing efficiency. These results could provide a better comprehension of the mechanics of RL in disordered media and emphasize the essential role of scatterer density in determining RL efficiency. Our work deepens the understanding of RL dynamics and lays the groundwork for designing and optimizing colloidal RL systems for various applications such as imaging and optical sensing.