تقرير
Efficient ultra-broadband low-resolution astrophotonic spectrographs
العنوان: | Efficient ultra-broadband low-resolution astrophotonic spectrographs |
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المؤلفون: | Gatkine, Pradip, Sercel, Greg, Jovanovic, Nemanja, Broeke, Ronald, Lawniczuk, Katarzyna, Passoni, Marco, Balakrishnan, Ashok, Bidnyk, Serge, Yin, Jielong, Jewell, Jeffrey, Wallace, J. Kent, Mawet, Dimitri |
سنة النشر: | 2024 |
المجموعة: | Astrophysics Physics (Other) |
مصطلحات موضوعية: | Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Instrumentation and Detectors, Physics - Optics |
الوصف: | Broadband low-resolution near-infrared spectrographs in a compact form are crucial for ground- and space-based astronomy and other fields of sensing. Astronomical spectroscopy poses stringent requirements including high efficiency, broad band operation ($>$ 300 nm), and in some cases, polarization insensitivity. We present and compare experimental results from the design, fabrication, and characterization of broadband (1200 - 1650 nm) arrayed waveguide grating (AWG) spectrographs built using the two most promising low-loss platforms - Si$_3$N$_4$ (rectangular waveguides) and doped-SiO$_2$ (square waveguides). These AWGs have a resolving power ($\lambda/\Delta\lambda$) of ~200, a free spectral range of ~ 200-350 nm, and a small footprint of ~ 50-100 mm$^2$. The peak overall (fiber-chip-fiber) efficiency of the doped-SiO$_2$ AWG was ~ 79\% (1 dB), and it exhibited a negligible polarization-dependent shift compared to the channel spacing. For Si$_3$N$_4$ AWGs, the peak overall efficiency in TE mode was ~ 50\% (3 dB), and the main loss component was found to be fiber-to-chip coupling losses. These broadband AWGs are key to enabling compact integrations such as multi-object spectrographs or dispersion back-ends for other astrophotonic devices such as photonic lanterns or nulling interferometers. Comment: 16 pages, 8 Figures, accepted for publication in Optics Express |
نوع الوثيقة: | Working Paper |
URL الوصول: | http://arxiv.org/abs/2404.02376 |
رقم الأكسشن: | edsarx.2404.02376 |
قاعدة البيانات: | arXiv |
الوصف غير متاح. |