High reflectance with steep reflection phase spectrum by guided-mode resonance

A guided-mode resonance mirror (GMRM) consisting of a subwavelength grating integrated in an optical waveguide on a highly reflective substrate was predicted to give interesting characteristics of high reflectance with a steep reflection-phase spectrum. This time, the characteristics were experimentally demonstrated for the first time. A GMRM of 1535 nm resonance wavelength was designed and fabricated for a vertically injected wave from the air with TE polarization. The reflectance was measured to be higher than ?1 dB over the wavelength from 1520 to 1560 nm. The reflection phase varied by ? for a wavelength change of 10 nm.