AN INJECTION-LOCKED ND-YAG LASER FOR THE INTERFEROMETRIC DETECTION OFGRAVITATIONAL-WAVES

In the Italian-french project VIRGO for the interferometric detection of gravitational waves, the laser source is an ultra-stabilized high-p ower CW laser. The shot-noise-limited sensitivity around the Fourier f requency of 200 Hz puts a limit to the laser power of about 1 kW By us ing the recycling configuration and an expected recycling gain of 100, the necessary laser power is relaxed to 25 W. This laser is operating with monomode output and injection locked by a low-power master oscil lator. We present a functional approach defining the laser system arch itecture as well as the first experimental results obtained with injec tion-locking of a diode-pumped Nd:YAG slab. The experimental results s how the feasibility of the injection-locking technique as a way to tra nsfer the stability of a frequency-stabilized master laser to a slave laser.