Cavity-resonator-integrated guided-mode resonance filter in channel waveguide

Abstract

A cavity-resonator-integrated guided-mode resonance filter (CRIGF) consisting of a grating coupler and a pair of distributed Bragg reflectors in a channel waveguide is proposed for a narrow-band reflection spectrum with a small aperture. A channel waveguide structure and grating pattern of the device were simultaneously formed by the electron-beam direct-writing lithography. A full-width at half-maximum of reflection spectrum of the fabricated CRIGF was about 0.3nm with the maximum reflectance of about 30%. A reflection phase varied by almost 2π for wavelength change of 1nm.