Birefringence control for ion-exchanged channel waveguides at 1.55 mu m wavelength

We show at 1.55 mu m wavelength that the waveguide birefringence of ion-exchanged channel waveguides in glass can be broadly tuned by a potassium and silver double-ion-exchange. Two different potassium and silver double-ion-exchange processes are used to make surface waveguides with negligible waveguide birefringence. This is of crucial importance in making devices for dense wavelength division multiplexing (DWDM) systems. The dependence of the waveguide birefringence on the channel width is also reported.