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The Review of Laser Engineering

Recent Progress in Quantum Optics. Generation of Bright Squeezed Light and Quantum-Correlated Twin Photon Beams Using a Semimonolithic Optical Parametric Oscillator.

Katsuyuki Kasai, Noriaki Onodera, Jiangrui Gao, Claude Fabre

Published Jan 1, 2000• 1 citation

Abstract

We have generated bright squeezed light and quantum-correlated twin photon beams by using a cw semimonolithic KTP Optical Parametric Oscillator (OPO), which exhibits a low oscillation threshold and is capable of oscillating even in the free-running (no external-feedback) condition. The pump beam reflected by the OPO, after a cascading nonlinearity process in the crystal, appears as bright squeezed light. The squeezing observed on the reflected pump beam from the semimonolithic OPO was 30% (inferred squeezing: 48%). The signal and idler beams generated by the optical parametric oscillator are highly quantum-correlated twin photon beams. Since the squeezing property of the intensity difference between the twin photonbeams is robust in the condition where the two fields are balanced, the squeezing can be observed even in the freerunning condition of the OPO. This intensity-difference squeezing observed between the twin photon beams from the free-running semimonolithic OPO was 70% (inferred squeezing: 87%).

DOI: 10.2184/lsj.28.690

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