A waveguide microring optical modulator

Electromagnetically induced transparency is accompanied by extraordinary dispersion that introduces slow light. In an optical cavity, this slow light dispersion can cause line center cavity pulling as well as pulse delay and resonance detuning in response to the associated modest excursion of the refractive index, magnified by the finesse of the cavity. The use of this nonlinear optical effect in a modulator device to transfer small amplitude electrical signals onto optical carriers is examined. Although many aspects of the concept fall short of useful targets, aspects of waveguide coupling and ring resonator design are revealed that could find utility in other device designs.