InAs-GaAs quantum pyramid lasers: In situ growth, radiative lifetimes and polarization properties
InAs-GaAs quantum pyramid lasers: In situ growth, radiative lifetimes and polarization properties
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DOI：
10.1143/jjap.35.1311
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发表时间：
1996-02-01
期刊：
影响因子：
--
通讯作者：
Heydenreich, J
中科院分区：
文献类型：
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作者：
Bimberg, D;Ledentsov, NN;Heydenreich, J
我们已经实现了基于InAs-GaAs和InGaAs-GaAs量子金字塔（QPs）的注入激光器，其横向尺寸从80到140埃不等。具有相对小的点（类似于80埃）的结构表现出先前预测的量子点（QD）激光器的性质，例如低阈值电流密度（低于100 Acm（-2））和低阈值特征温度（T-0 = 350-435 K）。当工作温度高于100-130 K时，由于量子点的载流子蒸发，T-0降低，阈值电流密度增加（室温下可达0.95-3.3 kAcm（-2））。较大的InAs量子点（类似于140埃）提供更好的载流子定位表现出饱和的基态发射和增强的非辐射复合率在高激发密度。在80-140埃的范围内，辐射寿命显示出对点尺寸的弱依赖性，分别接近于类似于1.8- 2ns。在由QP形状变换效应形成的垂直耦合量子点中实现了辐射寿命的显著降低。最后的安排对应于一个三维的四面体阵列的InAs岛插入在GaAs矩阵中，每个组成的几个垂直合并的InAs部分。我们第一次在这样的阵列中实现了注入激光。
We have realized injection lasers based on InAs-GaAs and InGaAs-GaAs quantum pyramids (QPs) with a lateral size ranging from 80 to 140 Angstrom. The structures with relatively small dots (similar to 80 Angstrom) exhibit properties predicted earlier for quantum dot (QD) lasers such as low threshold current densities (below 100 Acm(-2)) and ultrahigh characteristic temperatures (T-0 = 350-435 K). For operation temperatures above 100-130 K, T-0 decreases and the threshold current density increases (up to 0.95-3.3 kAcm(-2) at room temperature) due to carrier evaporation from QPs. Larger InAs QPs (similar to 140 Angstrom) providing better carrier localization exhibit saturation of the ground-state emission and enhanced nonradiative recombination rate at high excitation densities. The radiative lifetime shows a weak dependence on the dot size in the range 80-140 Angstrom being close to similar to 1.8-2 ns, respectively. A significant decrease in radiative lifetime is realized in vertically coupled quantum dots formed by a QP shape-transformation effect. The final arrangement corresponds to a three-dimensional tetragonal array of InAs islands inserted in a GaAs matrix each composed of several vertically merging InAs parts. We achieved injection lasing in such an array for the first time.