Advances on Polarization Modulator Technology and Methodology for Future Improvements

In this work we present the latest improvements on the fabrication of a non-crystal achromatic half-wave plate working in the sub-THz frequency range. This is achieved by hot-pressing polypropylene layers with photo-lithographed copper structures. We will discuss the performance of the first prototypes and a few techniques for the improvement of future designs. General considerations at the root of achromatic designs will also be touched upon which are valid for both optical and waveguide phase modulators.