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  • Experimental demonstration of frequency- downconverted arm-length stabilization for a future upgraded gravitational wave detector
Title: Experimental demonstration of frequency- downconverted arm-length stabilization for a future upgraded gravitational wave detector
Ground-based laser interferometric gravitational wave detectors (GWDs) consist of multiple optical cavity systems whose lengths need to be interferometrically controlled. An arm-length stabilization (ALS) system has played an important role in bringing these interferometers into an operational state and enhancing their duty cycle. The sensitivity of these detectors can be improved if the thermal noise of their test mass mirror coatings is reduced. Crystalline AlGaAs coatings are a promising candidate for this. However, the current ALS system with a frequency-doubled 532 nm light is no longer an option with AlGaAs coatings because the 532 nm light is absorbed by AlGaAs coatings due to the narrow bandgap of GaAs. Therefore, alternative locking schemes must be developed. In this Letter, we describe an experimental demonstration of a novel ALS scheme, to the best of our knowledge, which is compatible with AlGaAs coatings. This ALS scheme will enable the use of AlGaAs coatings in current and future terrestrial gravitational wave detectors.  more » « less
Award ID(s):
2207640
PAR ID:
10644553
Author(s) / Creator(s):
; ;
Publisher / Repository:
Optics Letters
Date Published:
Journal Name:
Optics Letters
Volume:
49
Issue:
20
ISSN:
0146-9592
Page Range / eLocation ID:
5763
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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