Coupled resonator optical waveguides (CROW)

We investigate theoretically and experimentally the characteristics, performance and possible applications of coupled resonator optical waveguides (CROWs). The ability to engineer the dispersion properties of a CROW and especially the ability to realize ultra-slow group velocities paves the way for various applications such as delay lines, optical memories and all-optical switching. Simple analytic expressions for the time delay, usable bandwidth and overall losses in CROW delay lines are derived and compared to exact numerical simulation. Good quantitative agreement is found between the theoretical transmission function obtained by transfer matrix formalism and the measurement of a CROW interferometer realized in polymer material.