Abstract

The generation of twin beams of light from an optical parametric amplifier (OPA) pumped by the second harmonic of a mode-locked and Q-Switched Nd:YAG laser has recently been reported.¹ The intensity noises on the direct- detected signal and idler beams at the output of the OPA were observed to be correlated by more than 15 dB, and the subtracted noise fell below the quantum limit by up to 7 dB (80%). With the same OPA it is much harder to generate and detect a highly squeezed beam of light.

© 1991 Optical Society of America