Title :
Polarization-independent thermooptic phase shifters in silicon-oxynitride waveguides
Author :
Offrein, B.J. ; Jubin, D. ; Koster, T. ; Brunschwiler, T. ; Horst, F. ; Wiesmann, D. ; Meijer, I. ; Petit, M. Sousa ; Webb, D. ; Germann, R. ; Bona, G.L.
Author_Institution :
IBM Res., Zurich Res. Lab., Ruschlikon, Switzerland
fDate :
6/1/2004 12:00:00 AM
Abstract :
The effective refractive index of dielectric waveguides can be tuned using the thermooptic effect. In general, the tuning efficiency is polarization-dependent owing to temperature-induced stress in the layers, which causes polarization-dependent loss in optical devices. These stress issues are analyzed and tested for a high-index-contrast waveguide structure based on a silicon-oxynitride core. Experimental results are in agreement with simulations. The relative difference in tuning efficiency for transverse electric and transverse magnetic polarized light can be tuned from -3% to +3% by appropriate waveguide technology control. The optimized thermooptic phase shifters show tuning efficiency differences below 0.25%, which are reproducible from wafer to wafer.
Keywords :
light polarisation; optical phase shifters; optical tuning; optical waveguides; refractive index; silicon compounds; thermo-optical devices; thermo-optical effects; SiON; dielectric waveguides; effective refractive index; high-index-contrast waveguide structure; optical devices; polarization-dependent loss; polarization-independent thermooptic phase shifters; silicon-oxynitride waveguides; thermooptic effect; transverse electric polarized light; transverse magnetic polarized light; tuning efficiency; waveguide technology control; Dielectrics; Optical devices; Optical losses; Optical polarization; Optical tuning; Optical waveguides; Phase shifters; Refractive index; Thermal stresses; Thermooptic effects;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2004.826729
