Stochastic resonance in linear regime of a single-mode laser

We present an analytic investigation of the signal-to-noise ratio by studying the linear model of a single-mode laser driven by coloured pump noise (tau(1)) and coloured quantum noise (tau(2)) with coloured cross-correlation (tau(3)), and obtain an exact analytic expression of the signal-to-noise ratio. We detect that the stochastic resonance occurs when the noise correlation coefficient lambda < 0. Furthermore, we analyse the effect of tau(1), tau(2) and tau(3) on the signal-to-noise ratio, and derive the condition under which the stochastic resonance occurs.