Cross-sectional STM study of InAs quantum dots for laser devices
Cross-sectional STM study of InAs quantum dots for laser devices
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用于激光器件的 InAs 量子点的横截面 STM 研究
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
M. Dähne
中科院分区：
文献类型：
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作者：
H. Eisele;O. Flebbe;T. Kalka;M. Dähne
我们展示了通过金属有机化学气相沉积生长的嵌入 GaAs 中的堆叠 InAs 量子点的横截面扫描隧道显微镜结果，最近已经证明了室温激光发射。五重堆叠显示出完美的垂直排列和层相关的点形状，这与生长过程中的局部应变有关。对于低隧道电压，观察到的波纹主要是由于 InAs 点和 GaAs 点的不同电子结构引起的，而在较高电压的情况下，观察到的点位置处的形貌高度更多地与解理表面处应变点的向外松弛有关。根据弹性理论对解理时应变松弛的数值模拟与观察到的突起高度非常吻合。
We present cross-sectional scanning tunnelling microscopy results of stacked InAs quantum dots embedded in GaAs grown by metal-organic chemical vapour deposition, for which room temperature lasing has been demonstrated recently. The fivefold stack shows a perfect vertical alignment and a layer-dependent dot shape, which is related to local strain during the growth process. For low tunnelling voltages, a corrugation mainly due to the different electronic structure of InAs dots and GaAs bost is observed, while in the case of higher voltages the observed topographic elevations at the dot positions are more related to an outward relaxation of the strained dots at the cleavage surface. A numerical simulation of strain relaxation upon cleavage by theory of elasticity agrees well with the observed heights of protrusions.