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Ω、高频载波频率ω和周期力频率Ωλ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Ω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≪ω时，系统出现的是多峰共振，且随着Ωλ增加，共振峰间的距离增大，峰值位置不变；当Ω→ω时，输出信噪比R迅速增大，而Ωλ的影响被削弱甚至可以忽略，多峰共振消失；当Ω=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。%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 frequencyΩ, the high-frequency carrier frequencyω, and the frequency of periodic forceΩλ have a significant effect on the SNR. In particular, multi-peak stochastic resonances and strong single-peak resonance with low-frequency modulation frequencyΩ appear in the SNR. WhenΩ≪ω, the system exhibits multi-peak resonance and the distance between the resonance peaks increases with the increase ofΩλ, but the position of peak is invariant. WhenΩ → ω, the output SNR R increases rapidly, the effect of Ωλ becomes weak or negligible, and multi-peak resonance disappears. When Ω = 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.
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