International Journal of Quantum Information
THREE-COLOR CONTINUOUS-VARIABLE ENTANGLEMENT DIRECTLY PRODUCED IN AN OPTICAL SUPERLATTICE
Youbin Yu, Zhongtao Shi, H. T. WANG, Yi-qiang Qin, Lingxiao Lai, S. H. JIN, Shining N. Zhu, Xiaoqiang Yu, Jianfeng Wang, Ping Xu, H. Y. Leng
Abstract
The three-color continuous-variable entanglement directly produced by a cascaded nonlinear process in an optical superlattice was investigated theoretically. This cascaded nonlinear process can be realized by using quasi-phase-matching technique in a quasiperiodic superlattice. In the first step, signal- and idle-beams can be generated by a parametric down-conversion. Then, the third beam can be obtained through sum-frequency of idle and pump. The degree of quadrature phase amplitude correlations between the three modes was discussed by a sufficient inseparability criterion with a single inequality for continuous-variable entanglement.