GaSb quantum rings in GaAs/AlxGa1-xAs quantum wells
GaSb quantum rings in GaAs/AlxGa1-xAs quantum wells
复制标题
GaAs/AlxGa1-xAs 量子阱中的 GaSb 量子环
DOI：
10.1063/1.4940880
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发表时间：
2016
影响因子：
3.2
通讯作者：
Hodgson P
中科院分区：
文献类型：
--
作者：
Hodgson P
报道了对嵌入在As/Al{subx}Ga{sub1−x}As量子阱中的第二类GaSb量子环的连续和时间分辨光致发光测量结果。用不同的势垒宽度、势垒内的补偿掺杂浓度和量子环层数生长了一系列样品。我们发现，除了最窄的(5 nm)量子阱外，所有这些变体对辐射复合都没有明显的影响。相比之下，样品的单粒子数值模拟预测了高达200 MeV的光致发光能量的变化。这种显著的差异是由于电子与带有空穴的环的强烈库仑结合所解释的。发射对补偿掺杂的弹性表明，量子环的多个空穴占据是有效的载流子复合所必需的，无论这些空穴来自掺杂还是激发。
We report the results of continuous and time-resolved photoluminescence measurements on type-II GaSb quantum rings embedded within GaAs/Al{sub x}Ga{sub 1−x}As quantum wells. A range of samples were grown with different well widths, compensation-doping concentrations within the wells, and number of quantum-ring layers. We find that each of these variants have no discernible effect on the radiative recombination, except for the very narrowest (5 nm) quantum well. In contrast, single-particle numerical simulations of the sample predict changes in photoluminescence energy of up to 200 meV. This remarkable difference is explained by the strong Coulomb binding of electrons to rings that are multiply charged with holes. The resilience of the emission to compensation doping indicates that multiple hole occupancy of the quantum rings is required for efficient carrier recombination, regardless of whether these holes come from doping or excitation.