Optical properties of metallo-dielectric deep trench gratings: role of surface plasmons and Wood-Rayleigh anomaly

摘要

We present optical measurements performed on a gold film deposited on deep subwavelength grooves etched in a quartz substrate at visible wavelengths where the Wood-Rayleigh (WR) anomaly and surface plasmon polaritons (SPs) are well separated. The measurements show that transmission of TM-polarized light through the slit array vanishes when SPs are excited at the air-metal interface, whereas the WR anomaly appears as small peaks.