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arXiv · 2306.10575

Six-telescope integrated optics beam combiner fabricated using ultrafast laser inscription for J- and H-band astronomy

Aline N. Dinkelaker·Sebastian Smarzyk·Abani S. Nayak·Simone Piacentini·Giacomo Corrielli·Roberto Osellame·Ettore Pedretti·Martin M. Roth·Kalaga Madhav
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Abstract

We have built and characterized the first six-telescope discrete beam combiner (DBC) for stellar interferometry in the astronomical J-band. It is the DBC with the largest number of beam combinations and was manufactured using ultrafast laser inscription (ULI) in borosilicate glass, with a throughput of approximately 56%. For calibration of the visibility-to-pixel matrix (V2PM), we use a two-input Michelson interferometer and extract the complex visibility. A visibility amplitude of 1.05 and relative precision of 2.9% and 3.8% are extracted for 1328 nm and 1380 nm, respectively. Broadband (< 40 nm) characterization is affected by dispersion, but shows similar performance.

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Aline N. Dinkelaker, Sebastian Smarzyk, Abani S. Nayak, Simone Piacentini, Giacomo Corrielli, Roberto Osellame, Ettore Pedretti, Martin M. Roth, Kalaga Madhav. 2023-06-18. Six-telescope integrated optics beam combiner fabricated using ultrafast laser inscription for J- and H-band astronomy. https://doi.org/10.1364/ao.499135

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