Tolerant polarization converter for InGaAsP-InP photonic integrated circuits

We report the fabrication and characterization of a new polarization converter for InGaAsP-InP photonic integrated circuits. The converter consists of two right trapezoidal sections with the angled sidewalls etched wetly. The converters show a greatly improved tolerance to variations of the fabrication, an averaged efficiency of polarization conversion of 99.8% and a loss of about 0.7 dB at a wavelength of 1.535 µm