Mueller matrix imaging of GaAs/AlGaAs self-imaging beamsplitting waveguides

Imaging polarimetry is a novel method of characterizing the polarization effects of optoelectronic devices. From the Mueller matrix image, any polarization property of a device can be determined. High resolution polarization images of the outcoupling faces of several self-imaging GaAs/AlGaAs waveguide beamsplitters were made in the Mueller Matrix Imaging Polarimeter at The University of Alabama in Huntsville. Interesting polarization effects were observed in these measurements. While the orientation of linear retardance was, uniformly aligned with the polarization states of the device modes (TE and TM), the magnitude of linear retardance varied significantly across a device. Polarization losses (diattenuation) were also observed to vary across the faces of the devices. These effects could not have been observed by simply measuring the crosstalk between the TE and TM modes. The results of this study could lead to the detection of defect mechanisms in optoelectronic devices through Mueller matrix measurements.