A two-mode squeezed light based on a double-pump phase-matching geometry

He Xuan-Jian¹, Jia Jun¹, Jiao Gao-Feng¹, Chen Li-Qing^{1, †}, Yuan Chun-Hua^{1, 3, ‡}, Zhang Wei-Ping^{2, 3}

The geometric phase matching for (a) a single pump field and (b) two pump fields. The angle between pump fields k_P₁ and k_P₂ is θ₀. The angles between the probe field k_p and the pump fields k_P₁ and k_P₂ are θ₁ and θ₂, respectively. Here θ₃ is the angle between the probe and the projected pump field. The frequency degenerate twin beams are generated with an exchange of the roles of the pump and probe beams.