We present a broadband plasma spray anti-reflection (AR) coating technology for millimeter-wave astrophysics experiments with large-format, cryogenic optics. By plasma spraying alumina- and silica-based powders, we have produced coatings of tunable index of refraction and thickness, low loss, and coefficient of thermal expansion matched to alumina substrates. We demonstrate two-layer AR coatings on alumina with reflection below 5% over 82% and 69% fractional bandwidths for 90/150 and 220/280 GHz passband designs, respectively, and band-averaged absorption loss reduced to
We present two prescriptions for broadband (
- NSF-PAR ID:
- 10142388
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 59
- Issue:
- 10
- ISSN:
- 1559-128X; APOPAI
- Page Range / eLocation ID:
- Article No. 3285
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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