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. The value and position of the effective mode
index within the region of static effective mode index remains substantially unchanged
over time. The optical waveguide couples the active optical waveguide device and
the passive optical waveguide device, and the optical waveguide is formed at least
in part using the semiconductor layer.
