Design and fabrication of metasurfaces for wavefront sensing and high-contrast imaging in the visible

Future large telescopes for exoplanet detection and characterization will require exquisite starlight suppression capabilities as well as the ability to maintain stability over long time scales in order to detect faint signals from planets of interest. Coronagraphs can be employed to block out starlight, and wavefront sensors are routinely used to align and maintain the stability of telescopes. In this work we demonstrate steps towards making focal plane masks that can support both these functions simultaneously; wavefront sensing in reflection and starlight suppression in transmission. By making use of metasurfaces, a high-order Zernike wavefront sensor with extended dynamic range can be implemented in reflection, while a Lyot style coronagraph is implemented in transmission. Here we demonstrate design and fabrication of the reflective wavefront sensing metasurface, while at the same time detailing compatibility of this mask with coronography in transmission.