SQUEEZING IN A QUASI-PHASE-MATCHED LINBO3 WAVE-GUIDE

We report traveling-wave quadrature squeezing at 1064 nm in a quasi-ph ase-matched LiNbO3 waveguide, avoiding the gain-induced diffraction en countered in bulk squeezing experiments. The 10-mm-long single-mode wa veguide parametric amplifier exhibited a gain of 1.9, averaged over th e 20-ps mode-locked pulses, with only 0.5 W of peak pump power at 532 nm. Independent waveguides were employed for the degenerate parametric amplifier squeezer and for the second-harmonic generator that produce d the pump for the parametric amplifier. We measured phase-sensitive a mplification versus pump power and found close agreement with theory. The observed 14% squeezing correlates closely with the predicted value , based on the measured phase-sensitive amplification and 40% overall detection efficiency. Impedance-matched electrically resonant detectio n was used to boost our Squeezing measurement signals substantially ab ove the background level. (C) 1995 Optical Society of America