Hill K O, Johnson D C, Kawasaki B S
Appl Opt. 1981 Mar 15;20(6):1075-9. doi: 10.1364/AO.20.001075.
The efficient conversion of 1.06-mum radiation in a graded-index multimode optical fiber oscillator into a small number of spectral components propagating in specific modes of the fiber and falling in the spectral range spanning from the blue to 1.53 mum is reported. The effect is shown to result primarily from phase-matched four-photon mixing. The converted light is found to propagate as individual fiber modes which are identified. The wavelengths of the spectral components of the output of the oscillator are governed primarily by fiber geometry. Analysis of the results also indicates the presence and gives a measure of the fiber-core birefringence sensed by low-order modes of propagation of the graded-index multimode fibers we have studied. The efficiency of the oscillator source and the specific characteristic wavelengths available with common graded-index fibers suggest several possible applications, which are discussed.
报道了在渐变折射率多模光纤振荡器中将1.06微米辐射高效转换为在光纤特定模式下传播且落入从蓝光到1.53微米光谱范围的少数光谱成分。结果表明，这种效应主要源于相位匹配的四光子混频。发现转换后的光以已识别的单个光纤模式传播。振荡器输出光谱成分的波长主要由光纤几何形状决定。对结果的分析还表明了我们所研究的渐变折射率多模光纤低阶传播模式所感知的光纤芯双折射的存在并给出了其测量值。振荡器源的效率以及普通渐变折射率光纤可用的特定特征波长表明了几种可能的应用，对此进行了讨论。
