Nonzeroth-order anomalous optical transparency in modulated metal films owing to excitation of surface plasmon polaritons: an analytical approach.
A. V. Kats, A. Yu. Nikitin1)
Usikov Institute for Radiophysics and Electronics NAS 61085 Kharkiv, Ukraine
PACS: 42.25.-p, 73.20.Mf, 78.20.-e
Abstract
The problem of anomalous light tunneling through
periodically modulated metal films is examined in a purely
analytical approach. The approach
uses large magnitude of the dielectric permittivity of metals in
the visible and near infrared (it is equivalent to that resulting
in the Leontovich boundary conditions for semi-infinite
problems). It is shown that the anomalous transparency recently
discovered experimentally is caused by the excitation of single-
or double-boundary surface plasmon polaritons due to film
modulation. Dependencies of the resonance transparency on
parameters of the problem are analyzed in detail, and the optimum
parameters (optimal layer thickness and optimal modulation
amplitude) corresponding to extreme values of the transmittance of
both zero and nonzero diffraction orders have been found.
Classifying the possible types of the resonances has allowed
identifying special and nontrivial features of the effect. In
particular, we predict strong nonzeroth-order anomalous
transparency.