
changes like the asymmetric directional coupler is. This coupler is the most compact
WPF-desensitized directional coupler. Unfortunately, this coupler appears to exhibit
significant polarization crosstalk when implemented in silica waveguides, and research
is ongoing to mitigate this.
9.2.3 Polarization Effects
Non-technical overview: The oscillating electric field that makes up the optical
signal can be oscillating predominantly either parallel to the PLC surface or
perpendicular to it and in the direction of propagation. Which direction the
electric field is oscillating determines its polarization. The light in PLCs usually
travels faster or slower ...