论文标题
分子束积液细胞质量对量子点和量子井的光学和电性能的影响
Influence of molecular beam effusion cell quality on optical and electrical properties of quantum dots and quantum wells
论文作者
论文摘要
最近，使用高纯度材料，具有出色低噪声特性的量子点异质结构成为可能。我们提出了一项有关分子束外延种植的量子孔和量子点的研究，并具有污染的铝蒸发细胞，该细胞引入了大量的杂质，在光学和电气测量中可感知的异常。我们描述了一种解决此问题的方法，并发现通过过热来重新调节铝细胞可以使光致发光和电容 - 电压测量的异常恢复，从而导致出色的低噪声异质结构。此外，我们提出了一种使用电容 - 电压光谱在自组装量子点上感知光诱导的陷阱电荷的方法。缺陷中心的激发能量依赖性电离导致电容 - 电压光谱的变化，该光谱可用于确定通过1D带结构模拟的光诱导陷阱电荷的电荷密度。该方法可以在常用的量子点二极管结构上执行。
Quantum dot heterostructures with excellent low-noise properties became possible with high purity materials recently. We present a study on molecular beam epitaxy grown quantum wells and quantum dots with a contaminated aluminum evaporation cell, which introduced a high amount of impurities, perceivable in anomalies in optical and electrical measurements. We describe a way of addressing this problem and find that reconditioning the aluminum cell by overheating can lead to a full recovery of the anomalies in photoluminescence and capacitance-voltage measurements, leading to excellent low noise heterostructures. Furthermore, we propose a method to sense photo-induced trap charges using capacitance-voltage spectroscopy on self-assembled quantum dots. Excitation energy-dependent ionization of defect centers leads to shifts in capacitance-voltage spectra which can be used to determine the charge density of photo-induced trap charges via 1D band structure simulations. This method can be performed on frequently used quantum dot diode structures.
