湍流对部分相干光光谱移动的影响

Wolf效应，即部分相干光除满足定标律之外，即使在自由空间中传输时其光谱一般也会发生变化，是一类著名的相关诱导光谱变化现象。以高斯-谢尔模型(GSM)光束作为部分相干光的典型例子，研究湍流对高斯-谢尔模型光束光谱移动的影响。基于部分相干光的传输定理，并考虑湍流的存在，推导出了高斯-谢尔模型光束通过湍流介质的光谱公式，并作了数值计算。研究表明，无论定标律是否满足，湍流都会影响高斯-谢尔模型光束的光谱。湍流越强，与无湍流情况比较光谱移动越大。特别是，若不满足定标律时轴外光谱还会出现分裂。高斯-谢尔模型光束在湍流介质中的光谱移动由光束的空问相干性、折射率结构常数Cn^2和位置等参量决定。

Effect of Turbulence on the Spectral Shift of Partially Coherent Light

The Wolf effect, i.e., the spectrum of par ti ally coherent light generally changes on propagation even in free space unless t he light obeys the scaling law, is a well-known phenomenon of the correlation- induced spectral changes. This paper deals with the influence of turbulence on t he spectral shift of the Gaussian Schell-model (GSM) beam, which is taken as a typical example of partially coherent light. Based on the propagation law of par tially coherent light and consideration of the presence of turbulence, an expres sion for the spectrum of GSM beams propagating through turbulence media is deriv ed and numerical calculations are performed. It is shown that the turbulence aff ects the spectrum of GSM beams, whenever the scaling law holds or does not hold true. The stronger the turbulence is, the larger spectral shift appears in compa rison to the case without turbulence. In particular, there is off-axis spectral splitting if the scaling law fails. The spectral shift of GSM beams in turbulenc e media depends on the beam spatial coherence, refraction index structure consta nt c2 n and position parameter in general.