FILTER TUNABLE BY MEANS OF EXTERNAL ELECTRIC FIELD
Anton I. Ignatov, Alexander M. Merzlikin
Institute for Theoretical and Applied Electromagnetics,
RAS. Moscow, Russia.
Received August 30, 2011
Abstract. A novel model of a tunable optical waveguide filter
based on a corrugated planar waveguide made of electrooptic material is
proposed. The principle of operation of the filter is based on à degenerate band gap manipulation. Degenerate band gaps form due to
coupling of TE and TM modes of the waveguide under the application of the
external electric field inducing the anisotropy of the waveguide material.
Characteristics of à degenerate band gap are analyzed
with the coupled mode method in approximation of the corrugation amplitude
being small compared to the waveguide thickness. The anisotropy is also
supposed to be weak. The proposed filter is much easier to fabricate than multilayer
Šolc filters whose physical principles of operation are analogous.
Key words: tunable optical filter, tunable optical switch,
corrugated waveguide, photonic crystal band gaps.