Patent ID: 6647158
Filing Date: 2003-11-11
Classification: G02F

Abstract:
An electro-optic push-pull modulator, comprising:a substrate; an electro-optic waveguide having a multiple quantum well (MQW) structure defined about the substrate, the waveguide having a crystal axis orientation, the waveguide having a first waveguide arm and a second waveguide arm, optical signals propagating through the waveguide, the optical signals having an optical polarization; each waveguide arm exhibiting refractive index changes, which vary quadratically in response to varying electrical fields applied to the waveguide arms substantially perpendicular to the MQW structure; each waveguide arm exhibiting further refractive index changes, which vary linearly in response to the varying electrical fields, the linear response determined by the crystal axis orientation of the waveguide and the optical polarization of the optical signals; and an electrode structure disposed about the substrate applying the varying electrical fields to each waveguide arm substantially perpendicular to the MQW structure, the electrode structure inducing opposite refractive index changes in the waveguide arms with an applied modulation voltage for push-pull modulation of the optical signals, the electrode structure biasing the electrical fields about an electrical field having a non-zero magnitude and a direction such that the linearly-varying and quadratically-varying refractive index changes add together.