Tunable narrow band optical reflector based on indirectly coupled micro ring resonators.

This paper presents a novel narrow band wavelength selective optical reflector implemented by indirectly coupling two micro ring resonators in silicon-on-insulator technology. The device is studied using an analytical model based on the transfer matrix method. With the proposed configuration, by electrically driving the integrated micro heaters, a single reflection wavelength with narrow bandwidth can be tuned. The experimental results show a good agreement with the model outcomes. The average measured reflectivity over a wavelength span of 37 nm is 0.55, with a peak of about 50 pm full-width-half-maximum, which corresponds to a quality factor of similar to 30, 000. The proposed device can offer an alternative approach to realize compact reflective structures for single wavelength reflection operations in photonic integrated circuits. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement