G. Heinzel et al., Experimental demonstration of a suspended dual recycling interferometer for gravitational wave detection, PHYS REV L, 81(25), 1998, pp. 5493-5496
The advanced scheme of "signal recycling" is to be used in the British-Germ
an GEO 600 project, in addition to "power recycling" (which has become stan
dard for all laser-interferometer gravitational wave detector projects). Th
is combination, "dual recycling," has been demonstrated for the first time
on a fully suspended interferometer, the Garching prototype with 30 m arm l
ength. Signal enhancement and power buildup were as predicted; operation wa
s reliable, and a significant contrast enhancement was observed. A control
system that can be extended to full scale gravitational wave detectors was
employed.