Abstract: An apparatus and associated method for altering the propagation constant of a region of equalizing propagation constant in an optical waveguide. The method comprising positioning an electrode of a prescribed electrode shape proximate the waveguide. An altered region of equalizing propagation constant is projected into the waveguide that corresponds, in shape, to the prescribed electrode shape by applying a voltage to the shaped electrode. The propagation constant of the region of equalizing propagation constant is controlled by varying the voltage.

Abstract: An optical waveguide device includes an active optical waveguide device and a passive optical waveguide device. The active optical waveguide device is formed at least in part on a semiconductor layer and includes an electrode portion. A region of altered effective mode index is created by the active optical waveguide device and controlled by application of an electric voltage to the electrode portion in a manner that alters a free carrier density of the region of altered effective mode index. Changing the electric voltage to the electrode portion changes the effective mode index in the region of altered effective mode index. The passive optical waveguide device is formed at least in part from a polysilicon layer deposited on the semiconductor layer. An effective mode index of a region of static effective mode index within the optical waveguide is created by the polysilicon layer of the passive optical waveguide device.