Single-pixel polarimeter: dielectric-gratings model and fabrication progress

Abstract

The single-pixel polarimeter design has been described in earlier work. The device consists of four (or more) multi-quantum-wells and gratings stacked above each other, and it measures instantaneously the incident light’s polarization for a narrow wavelength band. The four active regions of the quantum-wells are separated by linear gratings at different orientations. Electrical contact is made to each grating and to a bottom contact layer to measure four photocurrents. The device uses interference among the many light paths formed from multiple diffractions to encode in the four photocurrents the polarization state of the incident light. My previously reported computational model assumes the single-pixel polarimeter is fabricated with perfectly conducting gratings. Here, I present results from a model of the polarimeter with more realistic dielectric gratings. The model of the dielectric-grating polarimeter is compared to the model of the perfectly conducting grating polarimeter. Fabrication of the device may be accomplished by the etching of gratings followed by regrowth, or regrowth and chemical–mechanical polishing, or wafer-fusion. The different approaches to fabrication of this polarimeter will be compared, and our construction progress will be reviewed.