摘要:
在周期力调制噪声驱动下单模激光系统的光强方程中加入调幅波,用线性化近似方法计算了系统的光强关联函数和输出信噪比,并对信噪比进行数值计算和分析,发现低频调制频率?、高频载波频率ω和周期力频率?λ对系统的输出信噪比有很大的影响。具体表现为信噪比R随低频调制频率?的变化过程中出现了多重随机共振和极强的单峰共振,当??ω时,系统出现的是多峰共振,且随着?λ增加,共振峰间的距离增大,峰值位置不变;当?→ω时,输出信噪比R迅速增大,而?λ的影响被削弱甚至可以忽略,多峰共振消失;当?=ω时,系统出现了极强的单峰共振。此外,信噪比随周期力频率的变化呈现振幅减小的多重随机共振,而随载流频率的变化出现单峰随机共振。
Abstract:
Using the linear approximation method, we calculate the intensity correlation function and the output signal-to-noise ratio (SNR) by adding a modulated wave to light intensity equation of a single mode laser system driven by the periodic force of modulating noise. Through the numerical calculation and analysis of the SNR, we find that the low-frequency modulation frequency?, the high-frequency carrier frequencyω, and the frequency of periodic force?λ have a significant effect on the SNR. In particular, multi-peak stochastic resonances and strong single-peak resonance with low-frequency modulation frequency? appear in the SNR. When??ω, the system exhibits multi-peak resonance and the distance between the resonance peaks increases with the increase of?λ, but the position of peak is invariant. When? → ω, the output SNR R increases rapidly, the effect of ?λ becomes weak or negligible, and multi-peak resonance disappears. When ? = ω, a strong single-peak resonance appears in the system. In addition, the SNR varies with the decrease of amplitude of the multi-peak stochastic resonance, and with the SNR changes with carrier frequency the single-peak stochastic resonance appears in the system.