ABSTRACT
Because of their compact, essentially chip-scale sizes, optical microresonators have been attracting considerable theoretical and experimental attention. They have applications in fields ranging from fundamental physics to telecommunications systems [1]. As optical microresonators have the capability to store light in physically small volumes, we envision that periodic coupled microresonator structuresmay provide a newmethod for controlling the group velocity of optical pulses in a compact way on a chip. To this end, two main types of structures have been proposed: coupled-resonator optical waveguides (CROWs) [2,3] and side-coupled integrated sequence of spaced optical resonators (SCISSORs) [4,5]. A CROW is a chain of resonators in which light propagates by virtue of the direct coupling between the adjacent resonators (Figure 5.1a). In contrast, a SCISSOR consists of a chain of resonators that are not directly coupled to each other, but are coupled through at least one sidecoupled waveguide (Figure 5.1b). Both CROWs and SCISSORs have the potential to significantly slowdown the propagation of light.
