A Novel Approach to Detect Nanoparticle Concentration Using Active Cavity WGM Sensor

This paper presents a new approach to nanoparticle detection using an active micro-resonator operating in the transparency regime. Simulations demonstrate that when nanoparticles interact with the micro-resonator surface, they induce optical losses. To compensate for these losses, the optical gain is amplified to restore the transparency regime. Simulation results show a linear relationship between nanoparticle concentration and the pump power required to compensate for optical losses. By the use of micro-resonator with a very high quality factor, this approach offers an accurate and sensitive method for detecting nanoparticles, without the need for complex equipment.