Transmission and reflection navigated optical probe with depth-tuned surface corrugations

Abstract

An optical probe with a single aperture flanked by depth-tuned surface corrugations is presented. It can generate enhanced optical transmission at the exit of a slit and lower reflection at the top side of the compound dielectric/metal structure. The probe is designed and discussed on the basis of enhanced surface plasmon resonance for the purpose of high-resolution inspection use. A multidielectric probe consisting of air/glass/C/Ag/air is put forward. The influence of the thickness of the carbon film on the reduction of reflection is analyzed in detail combined with the relevant funneling effect induced by waveguide mode propagation through a central slit. Our simulation results show that a carbon film with a thickness of 150 nm and a 200-nm Ag film with the designed parabolic corrugations can reach our design target of the enhanced optical transmission and minimum reflection.