Crosstalk in optical waveguide switches/modulators caused by having two polarizations simultaneously present is studied in this work. This situation is expected to arise when fiber optical transmission lines are coupled to integrated optical circuits. Modulator/switch performance is found to be strongly affected by having two propagating polarizations. Conditions on device design are found that minimize the polarization sensitivity of switches/modulators, making them suitable for use with fiber optic transmission lines.
R. A. Steinberg and T. G. Giallorenzi, "Performance limitations imposed on optical waveguide switches and modulators by polarization," Appl. Opt. 15, 2440-2453 (1976)