This paper discusses a measurement scheme of high power twin beams generated by a non-degenerated optical parametric oscillator operating above threshold.

This paper discusses a time-domain measurement scheme of quantum correlation of twin beams generated by a non-degenerated optical parametric oscillator operating above threshold.

The twin beams with high quantum correlation at 1 08 μm wavelength have been generated from the semimonolithic KTP OPO pumped by a frequency doubled and frequency stabilized Nd∶YAP laser The parametric frequency down conversion with the type ⅠⅠ 90° noncritical phase matching has been achieved in the α cut KTP for the 0 54 μm pump power.

For example: 1, quadrature amplitude (or phase) squeezed light; 2, quantum correlation twin beam; 3, sub-poissonian light (or intensity squeezed light).