PAWS and POCO: NIR Astrophotonic Instruments for Astronomy

For near-infrared ground and space-based astronomy, compact photonic devices can replace the large bulk optical components in spectrographs, frequency combs, beam combiners, and sky subtraction filters, thus saving cost, reducing volume, weight, and power requirements. Photonic integrated circuits (PICs), analogous to integrated circuits (IC) in electronics, are particularly powerful to address innovative miniaturized solutions. Here, we demonstrate two new instrument prototypes: the Potsdam Arrayed Waveguide Spectrograph (PAWS) built around an array waveguide grating (AWG) PIC and Hawaii2RG detector, and the Potsdam Comb (POCO), a frequency comb generated by nonlinear processes in a micro-ring resonator photonic chip. PAWS is calibrated by the remotely located POCO via the fiber optic communication network of the Leibniz-Institute for Astrophysics Potsdam (AIP). The vision of future astrophotonic solutions for instrumentation is pointing toward hybrid solutions of PIC and detector arrays that hold the promise to dramatically change the layout of telescope focal plane instrumentation.