Light modulation with resonant grating–waveguide structures

Resonant grating-waveguide structures formed with InP/InGaAsP semiconductor materials were tested to show light modulation at a wavelength of 1.55 microm. Narrow, subnanometer resonant spectral bandwidths and a ratio of ref lected intensities between resonance and away from resonance of greater than 50 were measured. For a resonant structure with an area of 3 mm x 3 mm, the modulation frequency reached 5 MHz.