Four-wave mixing and biphoton generation in a two-level system.
We find that in a two-level system there are two kinds of four-wave mixing processes which destructively contribute to the third-order nonlinear susceptibility. In a paired-photon generation scheme by using a single retroreflected pump beam, these two processes occur with definite time orders. The biphoton temporal correlation, which is measured with a back-to-back geometry in a laser-cooled two-level atomic ensemble, shows a damped Rabi oscillation and photon antibunching. Without suppressing the background of Rayleigh scattering, the upper limit of Cauchy criteria is estimated.
Du
Shengwang
S
Edward L. Ginzton Laboratory, Stanford University, Stanford, California 94305, USA. dus@stanford.edu
Wen
Jianming
J
Rubin
Morton H
MH
Yin
G Y
GY