Study on laser interaction with metallic and dielectric nanoparticles in free space

Research results on the scattering and heat loss of metal and dielectric particles are presented when the visible laser irradiated nanoparticles with a radius of 100 nm. The particles used were silver and titanium as the metallic materials and Al₂O₃ as the dielectric material. Simulation results showed that the metal particles had an energy absorption of 10^-17 Watt while the dielectric particles had a lower value of 10^-19 Watt. By analyzing the direction of heat flux, it was found that the energy generated from inside a metallic particle radiated to the outside following the surface of the particle. However, the dielectric particles showed the form of the internally trapped exothermic energy. Simulation results showed that the metal particles generated a much larger amount of heat compared to that of the dielectric particles. The mechanism of the overall energy emission is similar to that of the macro scale. A detailed analysis was presented with the simulation results and theories.