A single-mode laser system with colored cross-correlated additive and multiplicative noise terms is considered. By the means of projection operator method, we study the effects of the cross-correlation time 'tau' and the cross-correlation intensity 'lambda' between noises on the normalized intensity correlation function C(s). It is found that if 'lambda'g0 ('lambda'l0), the normalized intensity correlation function C(s) increases (decreases) with increasing the cross-correlation time 'tau', and at large value of 'tau', the variation of the normalized intensity correlation function C(s) becomes small. With the increase of the net gain a0, C(s) exhibits a maximum when 'lambda' is larger. However, a minimum and a maximum appear on C(s) curves with the increase of a0 when 'lambda' becomes smaller and smaller.
A single-mode laser system with colored cross-correlated additive and multiplicative noise terms is considered. By the means of projection operator method, we study the effects of the cross-correlation time 'tau' and the cross-correlation intensity 'lambda' between noises on the normalized intensity correlation function C(s). It is found that if 'lambda'g0 ('lambda'l0), the normalized intensity correlation function C(s) increases (decreases) with increasing the cross-correlation time 'tau', and at large value of 'tau', the variation of the normalized intensity correlation function C(s) becomes small. With the increase of the net gain a0, C(s) exhibits a maximum when 'lambda' is larger. However, a minimum and a maximum appear on C(s) curves with the increase of a0 when 'lambda' becomes smaller and smaller.
The intensity correlation time T is studied for gain-noise model of a single-mode laser driven by colored pump noise and colored quantum noise with colored cross-correlation. By using the linear approximation method, we detect that there exist maximum (i.e. resonance) in the T-D and T-I0 curves when the noise correlation coefficien λ is positive; and there exist minimum (i.e. suppression) in the T-D curves and exist one minimum and one maximum in the T-I0 curves when λ is negative. When λ is zero, The intensity correlation time T increases monotonously with the increasing of the quantum noise intensity D and steady-state intensity I0. However, no matter what the value λ is, the intensity correlation time T decreases monotonously with the increasing of the periodic signal amplitude A and the attenuation coefficient γ. Furthermore, we analyze the effect of signal frequency Ω. and the cross-correlation time T3 on the intensity correlation time T, find that has little effect on the T-D, T-I0, T-A and T-γ curves, and T3 has great effects on the T-D, T-I0 and T-A curves but has little effect on the T-γ curves.
By using the linear approximation method, the intensity correlation function and the intensity correlation time are calculated in a gain-noise model of a single-mode laser driven by colored cross-correlated pump noise and quantum noise, each of which is colored. We detect that, when the cross-correlation between both noises is negative, the behavior of the intensity correlation function C(t) versus time t, in addition to decreasing monotonously, also exhibits several other cases, such as one maximum, one minimum, and two extrema (one maximum and one minimum), i.e., some parameters of the noises can greatly change the dependence of the intensity correlation function upon time. T3.
The intensity correlation time T is studied by employing a gain-noise model of a single-mode laser driven by coloured pump noise τ1 and coloured quantum noise τ2 with coloured cross-correlation τ3 with a bias signal modulation. By using the linear approximation method, we detect that a maximum (i.e. resonance) exists in the curves of the intensity correlation time T versus the noise intensities D and Q when the noise correlation coefficient λ is positive; and a minimum (i.e. suppression) exists in the T−D and T−Q curves when λ is negative. When λ is zero, T increases monotonously with increase of D and decreases monotonically with increase of Q. Furthermore, the curve of T versus the pump noise self-correlation time τ1 is also studied. Our study shows that, no matter what the value of λ is, there exist one maximum and one minimum in the T−τ1 curve.
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 noise with 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 process from the monotonous descending to monotonous rise, and finally to 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 the increase of the pump noise intensity P , the curve experiences a repeated changing process, that is, from the monotonous descending to the appearance of a maximum, then to monotonous rise, and finally to the appearance of a maximum again. With the increase of the quantum noise intensity Q , the curve experiences a changing process from the monotonous rise to the appearance of a maximum, and finally to the monotonous descending. The increase of the quantum noise with cross-correlation between the real and imaginary parts will lead to the fall of the whole curve, but not affect the form of the time evolution of C ( t ).
The effect on intensity correlation time T by input signal is studied for gain-noise model of a single-mode laser driven by colored pump noise and colored quantum noise with colored cross-correlation with a bias signal modulation in this paper. By using the linear approximation method, we detect that there exists maximum (i.e., resonance) in the curve of the intensity correlation time T upon bias current i 0 when the noise correlation coefficient λ is positive; and there exists minimum (i.e., suppression) in the T - i 0 curve when λ is negative. And when λ is zero, T increases monotonously with increasing i 0 . Furthermore, the curve of T upon the signal frequency Ω is also studied. Our study shows that no matter what the value of λ is, there exists minimum (i.e., suppression) in the T -Ω curve.
In this paper, the intensity correlation time T is studied for the gain-noise model of a single-mode laser driven by coloured pump noise and coloured quantum noise with coloured cross-correlation with a direct signal modulation. By using the linear approximation method, it is found that when the pump noise is modulated directly by a signal, the effects of the cross-correlation between the pump noise and the quantum noise will disappear. In addition, there exists a maximum (i.e. resonance) in the curve of the intensity correlation time T versus the pump noise self-correlation time τ1. Furthermore, when τ1≤τ2, the intensity correlation time T increases monotonically with the increase of D and decreases monotonically with the increase of Q, but when τ1>τ2, the intensity correlation time T increases monotonically with the increase of Q and decreases monotonically with the increase of D.