Zhu Yanming, Zheng Wei, Ran Junxue, Huang Feng
Opt Lett. 2020 Apr 1;45(7):1719-1721. doi: 10.1364/OL.387256.
In this Letter, we describe an aperiodic-oscillation emission phenomenon originating from the Fabry-Perot effect in the deep-ultraviolet backscattering fluorescence spectrum of the $c$c-plane AlGaN film, which is related to the dispersion of its ordinary refractive index near the band edge. Based on this fluorescence spectrum, the ordinary refractive index of the AlGaN film near the band edge could be directly obtained. Certainly, by means of variable angle spectroscopic ellipsometry, the ordinary refractive index of the AlGaN film could be also achieved. Comparing the results obtained by both methods, we discovered that the refractive indices are quite similar, which suggests that the aperiodic-oscillation fluorescence spectrum is also a reliable approach to capture the refractive index of anisotropic optical films.
在本信函中，我们描述了一种源于c面AlGaN薄膜深紫外背散射荧光光谱中法布里 - 珀罗效应的非周期振荡发射现象，该现象与带边附近其寻常折射率的色散有关。基于此荧光光谱，可直接获得带边附近AlGaN薄膜的寻常折射率。当然，借助可变角度光谱椭偏仪也可得到AlGaN薄膜的寻常折射率。比较两种方法所得结果，我们发现折射率非常相似，这表明非周期振荡荧光光谱也是获取各向异性光学薄膜折射率的可靠方法。
