Development of an integrated near-IR astrophotonic spectrograph


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Gatkine P., Sitaram M., Veilleux S., Dagenais M., Bland-Hawthorn J.

Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation IV 2020, Virtual, Online, Amerika Birleşik Devletleri, 14 - 22 Aralık 2020, cilt.11451 identifier identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Cilt numarası: 11451
  • Doi Numarası: 10.1117/12.2561748
  • Basıldığı Şehir: Virtual, Online
  • Basıldığı Ülke: Amerika Birleşik Devletleri
  • Anahtar Kelimeler: Arrayed Waveguide Gratings, Cross-dispersion, Integrated Spectrograph, Near-IR, Photonic Lanterns, Photonic spectrograph
  • Galatasaray Üniversitesi Adresli: Hayır

Özet

© 2020 SPIE.Here, we present an astrophotonic spectrograph in the near-IR H-band (1.45-1.65 μm) and a spectral resolution (λ/δλ) of 1500. The main dispersing element of the spectrograph is a photonic chip based on Arrayed-Waveguide-Grating technology. The 1D spectrum produced on the focal plane of the AWG contains overlapping spectral orders, each spanning a 10 nm band in wavelength. These spectral orders are cross-dispersed in the perpendicular direction using a cross-dispersion setup which consists of collimating lenses and a prism and the 2D spectrum is thus imaged onto a near-IR detector. Here, as a proof of concept, we use a few-mode photonic lantern to capture the light and feed the emanating single-mode outputs to the AWG chip for dispersion. The total size of the setup is 50 cm x 30 cm x 20 cm3, nearly the size of a shoebox. This spectrograph will pave the way for future miniaturized integrated photonic spectrographs on large telescopes, particularly for building future photonic multi-object spectrographs.