Behavior of evanescent fields in the periodic scattering system
TOYOTA Central Research and Development Laboratories, Inc., Nagakute, Aichi 480 1192, Japan
a e-mail: firstname.lastname@example.org
Revised: 30 November 2011
Accepted: 30 January 2012
Published online: 23 February 2012
We study the problem of scattering by a thin and conducting screen perforated periodically with square apertures, when the screen is illuminated by an electromagnetic wave in subwavelength regime. Our formulation extends the monomodal approximation technique up to the second-order Floquet modes, which enable us to investigate not only propagation mode, but also nonpropagation mode in the low-frequency regime. We also study dispersion relation of the principal Floquet modes and show the behavior of electromagnetic fields in the periodic system at the extremely low frequency, the resonance frequency and Wood’s anomaly frequency. The interesting characteristics of the fields can be found in these specific frequencies.
© EDP Sciences, 2012