建立了一个由量子噪声和非线性色抽运噪声共同驱动下的单模激光立方模型,并将其在极坐标下分解为场幅和相位的朗之万方程(LE)。采用近似福克-普朗克方程的方法处理相位朗之万方程中的色噪声,使其马尔科夫化。将马尔科夫化后的相位朗之万方程与锁相条件相结合,得到稳定锁相值。详细讨论了量子噪声实虚部间的关联和抽运噪声实虚部间的关联对激光锁相的影响。结果表明激光锁相由量子噪声实虚部之间的关联引起,而抽运噪声实虚部间的关联和量子噪声实虚部间的关联均可改变这一锁相。
A cubic model of single-mode laser driven by quantum noise and nonlinear colored pump noise is founded, and the model is divided into amplitude Langevin equation (LE) and phase LE in polar coordinate. The approximate Fokker-Planck equation method is adopted to process the colored noise of phase LE, which makes the colored noise a Markovian process. Combined the equivalent phase LE which has been Markovian with phase locked conditions, the stable phase locked value is obtained. The effects of cross-correlation between the real and imaginary parts of pump noise and quantum noise on phase locked of single mode laser are discussed. Results reveal that the phase locked of laser is induced by the cross-correlation between the real and imaginary parts of quantum noise. However, the change of phase locked arises from the cross-correlation between the real and imaginary parts of pump noise or quantum noise.