We propose a new type of optical waveguide that consists of a sequence of coupled high-<i>Q</i> resonators. Unlike other types of optical waveguide, waveguiding in the coupled-resonator optical waveguide (CROW) is achieved through weak coupling between otherwise localized high-<i>Q</i> optical cavities. Employing a formalism similar to the tight-binding method in solid-state physics, we obtain the relations for the dispersion and the group velocity of the photonic band of the CROW's and find that they are solely characterized by coupling factor <i>k</i><sub>1</sub> . We also demonstrate the possibility of highly efficient nonlinear optical frequency conversion and perfect transmission through bends in CROW's.
© 1999 Optical Society of America
Amnon Yariv, Yong Xu, Reginald K. Lee, and Axel Scherer, "Coupled-resonator optical waveguide: a proposal and analysis," Opt. Lett. 24, 711-713 (1999)