Generation of squeezed vacuum states by PPKTP crystal and its Wigner quasi-probability distribution function reconstruction

Abstract

We demonstrated experimentally the generation of squeezed vacuum by a periodically poled KTP crystal in a continuous-wave optical parametric oscillator，which was pumped with 532nm field. The squeezed vacuum of 3.41 dB at 1064 nm was detected by a homodyne detection system. Moreover，the Wigner quasi-probability distribution function of the squeezed vacuum was reconstructed using quantum tomography technique.