Precise analysis of Wood-Rayleigh anomalies in the terahertz transmission spectrum of a metallic hole array

We derive a general expression for calculating the parameters of excitation of Wood and Rayleigh anomalies observed in the transmission spectrum of a hole array with square cells. An experimental validation of the model, using THz time-domain spectroscopy, is performed. The difference between s and p polarized transmitted signals allows us to clearly identify the signature of surface plasmon excitation.