Optical tunneling effect of localized surface plasmon: A simulation study using particle-in-cell method

Optical tunneling through thin metal films with periodic Gaussian-shaped grooves was studied using the particle-in-cell method. For a normally incident TM-polarized wave, the transmission coefficients are maximal in the localized surface plasmon (LSP) modes, which is similar to the predictions of the Drude model, but with lower transmission coefficients. The plasma-plasma interactions partially smear out the LSP modes, which has not been addressed in previous studies that involved the Drude model. Although various heating and cooling processes occur at the air-plasma interface, the temperature of the plasma only slightly affects the transmission coefficients.