Nonlinear laser absorption on metal surface embedded with nanoparticles in the presence of external magnetic field

Abstract

A nonlinear analytical model is developed for the absorption of a p-polarized laser that is obliquely incident on a metal surface embedded with metallic nanoparticles under the influence of an external magnetic field. The model suggests that the absorption coefficient is proportional to the angle of incidence and cube of nanoparticle-radius, but inversely proportional to the square of interparticle separation. Obtained results show that the laser absorption by the nanoparticles is substantially amplified due to plasmon resonance in the presence of an external magnetic field. The absorption coefficient has a sharp peak at surface plasma resonance ω=ωp/3, where ωp is the plasma frequency and it shows explicit dependence on the amplitude transmission coefficient TA of the incident wave. Absorption coefficient is obtained for gold nanoparticles for different incident angles, radii and interparticle separations and this study is of direct relevance in high performance optoelectronic devices, solar cells and nanomedicines.