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arXiv · 2506.06245

Metasurface-Enabled Astronomical Polarimetry

Lisa W. Li·Phillip H. H. Oakley·Rebecca N. Schindhelm·Sean G. Sellers·Roberto Casini·Noah A. Rubin
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Abstract

In the last decade or so, metasurface optical components have received considerable scientific and industrial interest for a variety of applications. The miniaturization afforded by metasurfaces could benefit astronomy in particular (which is an often-cited potential application area for metasurfaces). However, few developed examples in which metasurface components offer a unique benefit to astronomical instrumentation - substantiated by the production of scientific data - have been shown. Here, we present the Solar Imaging Metasurface Polarimeter (SIMPol), a first-of-its-kind telescope for snapshot imaging polarimetry of the sun around a Sr I line at 460.7 nm enabled by a metasurface polarization-analyzing grating. This high-performance grating exhibits an overall efficiency of nearly 70% and high polarization contrast (diattenuation) across its four observation channels. We demonstrate SIMPol's integration into a major observatory telescope facility with two different imaging modes. In both cases, Zeeman polarization signatures were clearly observed in two adjacent spectral lines of Fe I and Sr I around 460.7 nm. This work demonstrates an early success of metasurface polarization optics in a real application in astronomical instrumentation (here, polarimetric observations of the solar atmosphere), and heralds the application of metasurfaces and emergent nanophotonic technologies in astronomy more broadly.

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Lisa W. Li, Phillip H. H. Oakley, Rebecca N. Schindhelm, Sean G. Sellers, Roberto Casini, Noah A. Rubin. 2025-06-06. Metasurface-Enabled Astronomical Polarimetry. https://arxiv.org/abs/2506.06245

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