The Effects of Single-Mode Coherent and Squeezed Lights on Nondegenerate Three-level Laser

We consider a nondegenerate three-level laser in which the three-level atoms are in a cascade configuration, the laser cavity contains a degenerate parametric oscillator, and one of the cavity modes is driven by coherent light. We have analyzed the effects of the degenerate parametric oscillator and the driving coherent light on the laser using the expectation values of the cavity mode variables at a steady state. The results show that the two-mode light produced by the system under consideration exhibits quadrature squeezing. The presence of nonlinear crystal in the laser cavity generates a single-mode squeezed light and also enhances the degree of squeezing of the two-mode light. Although the driving coherent light has no effect on quadrature squeezing, it increases the intensity of the cavity modes.