Third- and Higher-Order Intensity Correlations in Laser Light
The statistics of single-mode laser light in the threshold region have been the subject of considerable experimental and theoretical study. The steady-state statistics are found to be well described by essentially the simplest physically reasonable model, the rotating-wave van der Pol (RWVP) model. However, the time-dependent statistical behavior of a laser, as it relaxes towards equilibrium from a fluctuation, involves considerably more details of its dynamics than does the time-independent steady-state behavior. Experimentally, the relaxation processes are revealed in the time dependence of the multi-time correlations of the intensity such as <I(t1)I(t2)> and <I(t1)I(t2)I(t3)>. In this paper we shall calculate the third-and higher-order intensity correlations,  which are more sensitive to the higher decay rates of the laser than the well-studied second-order intensity correlation. This will provide a more detailed understanding and test of the RWVP model.
KeywordsCoherence Time Threshold Region Intensity Correlation Intensity Cumulant Comparison Plot
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