High-power photo-detection system for next-generation gravitational wave detectors

Abstract

In next-generation interferometric gravitational wave detectors that are being designed, the power of their light sources will be larger than 100 W. As a consequence, the light power at the detection port of the interferometers must be increased by a factor of more than 10, compared with that of the current detectors; thus, a high-power photo-detection system is indispensable. Here, we present the photo-detection system which can detect the laser power of 500 mW at 1064 nm with a single photodiode of 3-mm diameter. Its response to DC and AC input signals are reported.