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arXiv · 1604.08355

Mid-IR AGPMs for ELT applications

Brunella Carlomagno·Christian Delacroix·Olivier Absil·Pontus Forsberg·Serge Habraken·Aïssa Jolivet·Mikael Karlsson·Dimitri Mawet·Pierre Piron·Jean Surdej·Ernesto Vargas Catalan
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Abstract

The mid-infrared region is well suited for exoplanet detection thanks to the reduced contrast between the planet and its host star with respect to the visible and near-infrared wavelength regimes. This contrast may be further improved with Vector Vortex Coronagraphs (VVCs), which allow us to cancel the starlight. One flavour of the VVC is the AGPM (Annular Groove Phase Mask), which adds the interesting properties of subwavelength gratings (achromaticity, robustness) to the already known properties of the VVC. In this paper, we present the optimized designs, as well as the expected performances of mid-IR AGPMs etched onto synthetic diamond substrates, which are considered for the E-ELT/METIS instrument.

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Brunella Carlomagno, Christian Delacroix, Olivier Absil, Pontus Forsberg, Serge Habraken, Aïssa Jolivet, Mikael Karlsson, Dimitri Mawet, Pierre Piron, Jean Surdej, Ernesto Vargas Catalan. 2016-04-28. Mid-IR AGPMs for ELT applications. https://doi.org/10.1117/12.2056280

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