Influence of Noise on Time Evolution of Intensity Correlation Function

Using the linear approximation method, we have studied how the correlation function C(t) of the laser intensity changes with time in the loss-noise model of the single-mode laser driven by the colored pump noise with signal modulation and the quantum noisewith cross-correlation between the real and imaginary parts. We have found that when the pump noise self-correlation time τ changes, (i) in the case of τ＜＜1, the C(t) vs. t curve experiences a changing processfrom the monotonous descending to monotonous rise, and finallyto the appearance of a maximum; (ii) in the case of τ＞＞1, the curve only exhibits periodically surging with descending envelope. When τ＜＜1 and τ does not change, with theincrease of the pump noise intensity P, the curve experiences arepeated changing process, that is, from the monotonous descending tothe appearance of a maximum, then to monotonous rise, and finally to theappearance of a maximum again. With the increase of the quantum noiseintensity Q, the curve experiences a changing process from the monotonousrise to the appearance of a maximum, and finally to the monotonousdescending. The increase of the quantum noise with cross-correlationbetween the real and imaginary parts will lead to the fall ofthe whole curve, but not affect the form of the time evolutionof C(t).