In this paper, we propose a multilayer arrayed waveguide gratings (AWG) for spectro-interferometry applications which were fabricated using the femtosecond laser direct writing technique. Individually these devices consisted on an array of 19 single mode waveguides, were designed for operation at 633nm, and have a measured free spectral range of 28nm and a resolution of 4 nm. The aim of this work is to show the potential of arrayed waveguides gratings (AWG) stacked in a vertical layered structure, in order to simultaneously achieve spectral dispersion and multi-telescope interferometry for astrophotonic applications (visibility vs baseline as a function of wavelength). In particular, with the fabrication of three independent AWG, we can address closure phase studies, an important tool for exoplanet detection in astronomy.
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