K. Arai et al., New signal extraction scheme with harmonic demodulation for power-recycledFabry-Perot-Michelson interferometers, PHYS LETT A, 273(1-2), 2000, pp. 15-24
We present a new signal-extraction scheme based on harmonic demodulation fo
r control of a power-recycled interferometric gravitational-wave detector.
Demodulation at the third-harmonic frequency of a frontal phase modulation
is used to robustly extract well-separated longitudinal signals. (C) 2000 E
lsevier Science B.V. All rights reserved.