The bandgap energy of InGaN alloy materials can be controlled by changing their alloy composition. Since the compositional fluctuation in the InGaN quantum wells (QWs) greatly affects the characteristics of optical devices, it is very important to understand the electronic structures of such fluctuated InGaN-QW systems for the improvement of their device characteristics. Mobility edge (ME), which is the boundary energy between the localized and delocalized states, can be an index to evaluate the potential fluctuation of carriers. Although several experiments have been proposed to evaluate the ME, they give sometimes different results. In this study, we experimentally and theoretically have studied the evaluation method of ME, and have revealed that the commonly-used evaluation method does not necessarily give accurate results. It is suggested that the method using photoluminescence excitation measurement is the best way to estimate the ME in InGaN-QWs

中文翻译：

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InGaN量子阱层中电势涨落的实验研究和模型分析

InGaN合金材料的带隙能量可以通过改变其合金成分来控制。由于InGaN量子阱（QW）中的成分波动极大地影响了光学器件的特性，因此了解这种波动的InGaN-QW系统的电子结构对于改善其器件特性非常重要。移动边缘（ME）是局部状态和离域状态之间的边界能量，可以作为评估载流子潜在波动的指标。尽管已提出了一些评估ME的实验，但有时会得出不同的结果。在这项研究中，我们通过实验和理论上研究了ME的评估方法，并揭示了常用的评估方法不一定能得出准确的结果。