Zhang Liyao, Song Yuxin, Chen Qimiao, Zhu Zhongyunshen, Wang Shumin
Department of Physics, University of Shanghai for Science and Technology, Shanghai 200093, China.
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Shanghai 200050, China.
Nanomaterials (Basel). 2018 Sep 10;8(9):705. doi: 10.3390/nano8090705.
InPBi thin film has shown ultra-broad room temperature photoluminescence, which is promising for applications in super-luminescent diodes (SLDs) but met problems with low light emission efficiency. In this paper, InPBi quantum dot (QD) is proposed to serve as the active material for future InPBi SLDs. The quantum confinement for carriers and reduced spatial size of QD structure can improve light emission efficiently. We employ finite element method to simulate strain distribution inside QDs and use the result as input for calculating electronic properties. We systematically investigate different transitions involving carriers on the band edges and the deep levels as a function of Bi composition and InPBi QD geometry embedded in InAlAs lattice matched to InP. A flat QD shape with a moderate Bi content of a few percent over 3.2% would provide the optimal performance of SLDs with a bright and wide spectrum at a short center wavelength, promising for future optical coherence tomography applications.
磷化铟铋薄膜已展现出超宽的室温光致发光特性，这使其在超发光二极管（SLD）应用中颇具前景，但存在发光效率低的问题。本文提出将磷化铟铋量子点（QD）用作未来磷化铟铋超发光二极管的活性材料。量子点结构对载流子的量子限制以及减小的空间尺寸能够有效提高发光效率。我们采用有限元方法模拟量子点内部的应变分布，并将该结果作为计算电子特性的输入。我们系统地研究了涉及能带边缘和深能级上载流子的不同跃迁，这些跃迁是铟铋组成以及嵌入与磷化铟晶格匹配的铟铝砷中的磷化铟铋量子点几何形状的函数。具有适度铋含量（超过3.2%的百分之几）的扁平量子点形状，将为超发光二极管提供最佳性能，在短中心波长处具有明亮且宽的光谱，这对未来的光学相干断层扫描应用很有前景。
