File(s) not publicly available
Polypropylene embedded metal mesh broadband achromatic half-wave plate for millimetre wavelengths
journal contributionposted on 2023-07-26, 13:59 authored by Jin Zhang, Peter A. R. Ade, Philip D. Mauskopf, Giorgio Savini, Lorenzo Moncelsi, Nicola Whitehouse
We describe a novel multilayered metal-mesh achromatic half-wave plate (HWP) for use in astronomical polarimetric instruments. The HWP is designed to operate across the frequency range from 125 to 250 GHz. The wave plate is manufactured from 12 layers of thin film metallic inductive and capacitive grids patterned onto polypropylene sheets, which are then bonded together using a hot-pressing technique. Transmission line modeling and three-dimensional electromagnetic simulations are used to optimize the parameters of the metal-mesh patterns and to evaluate their optical properties. A prototype HWP has been fabricated, and its performance is characterized in a polarizing Fourier transform spectrometer. The device performance is consistent with the modeling, although the measured differential phase shift for two orthogonal polarizations is lower than expected. This difference is likely to result from imperfect patterning of individual layers and misalignment of the grids during manufacture.
Publication titleApplied Optics
PublisherOptical Society of America