Quantum Entanglement of Twin Light Beams

摘要

A detailed quantum entanglement of twin light beams with the same and different frequencies produced by the process of parametric oscillation has been presented. We have described the process of the parametric oscillation with first-order Hamiltonian regardless of whether the twin light beams have the same or different frequencies. According to our study we have the quadrature variance decreases with the amplitude of pump mode and it approaches to the value of the quadrature variance of a two-mode vacuum state as cavity damping constant approaches to 1. In addition to this the degree of entanglement of the cavity modes for the system under consideration increase with the amplitude of the pump mode and decrease with the cavity damping constant, which implies that the degree of entanglement of twin light beams decreases as quadrature variances approaches to that of a two-mode vacuum state.