Schemes for controlling optical signals in optically functional waveguide structures

Abstract

Methods of attenuating, delaying the phase, and otherwise controlling an optical signal propagating along a waveguide are provided. According to one method, a variable optical attenuator structure is provided comprising a waveguide core, a cladding, an electrooptic polymer, and a set of control electrodes. The core, the cladding, and the electrooptic polymer are configured such that an increase in the index of refraction of the polymer causes a substantial portion of an optical signal propagating along the waveguide core to couple into a relatively high index region of the electrooptic polymer above the waveguide core, so as to inhibit return of the coupled signal to the waveguide core. Another embodiment of the present invention introduces a phase delay in the coupled optical signal and permits return of the coupled signal to the waveguide core. An additional embodiment contemplates the use of a ridge waveguide structure to enable control of the optical signal. Additional embodiments are disclosed and claimed.