Transverse-electric/transverse-magnetic polarization converter using twisted optic-axis waveguides in poled polymers

Polymeric passive TE/TM polarization converters are fabricated based on an adiabatic following in twisted optic-axis waveguides. Waveguides are formed by a reactive ion etching, and the optic axis of the waveguide is twisted by 90 degrees with specially designed poling electrodes. Both TE and TM modes confined in the waveguides are converted to their counterparts by following the twisted ordinary and extraordinary axes, respectively. Conversion efficiency better than 20 dB and polarization-dependent loss less than 0.5 dB are obtained. The device provides wavelength insensitive operations and has large fabrication tolerances. (C) 1997 American Institute of Physics.