United States Army Research Laboratory, Adelphi, Maryland, USA.
Opt Lett. 2012 Feb 15;37(4):683-5. doi: 10.1364/OL.37.000683.
Rayleigh scattering in optical fibers has the potential to degrade the performance of low-noise opto-electronic systems. In this Letter, we measure the Rayleigh gain spectrum of optical fibers. Our data show the gain bandwidth and the offset frequency of the Rayleigh gain peak. Both the gain bandwidth and the peak frequency are 3 orders of magnitude lower than the corresponding values for bulk silica. Our data suggest that the narrower gain bandwidth and frequency shift that we observe are due to guided entropy modes in the fiber. This effect is fundamental and will be present in any medium in which light is guided so that transverse intensity gradients exist.
光纤中的瑞利散射有可能降低低噪声光电系统的性能。在这封信中，我们测量了光纤的瑞利增益谱。我们的数据显示了瑞利增益峰的增益带宽和偏移频率。增益带宽和峰值频率都比块状石英低三个数量级。我们的数据表明，我们观察到的较窄的增益带宽和频率偏移是由于光纤中的导模熵模式。这种效应是基本的，将存在于任何存在光导且存在横向强度梯度的介质中。
