Nanoscopic recombination processes in InGaN/GaN quantum wells emitting violet, blue, and green spectra
Nanoscopic recombination processes in InGaN/GaN quantum wells emitting violet, blue, and green spectra
复制标题
DOI：
10.1103/physrevb.78.125317
复制
发表时间：
2008-09-01
影响因子：
3.7
通讯作者：
Kawakami, Y.
中科院分区：
文献类型：
--
作者：
Kaneta, A.;Funato, M.;Kawakami, Y.
利用扫描近场光学显微镜（SNOM）和原子力显微镜（AFM）研究了In（x）Ga（1-x）N/GaN量子威尔斯阱（QWs）中紫光、蓝光和绿光发射的纳米光学和结构特性之间的相关性。只有在蓝光量子阱中，穿透位错不是主要的非辐射复合中心。SNOM数据表明，在蓝色发光量子阱中的NRC被高于辐射复合的能级所包围。这样的电位分布实现了载流子对NRC的“反定域化”，这是蓝光发射体中高发射量子效率的原因。
We investigated correlations between nanoscopic optical and structural properties in violet-emitting, blue-emitting, and green-emitting In(x)Ga(1-x)N/GaN quantum wells (QWs) by means of scanning near-field optical microscopy (SNOM) and atomic force microscopy. Only in the blue-emitting QW, threading dislocations were not major nonradiative recombination centers (NRCs). SNOM data indicated that NRCs in the blue-emitting QW are surrounded by energy levels higher than those for radiative recombination. Such potential distributions realize "antilocalization" of carriers to NRCs, which is the cause of high emission quantum efficiencies in blue emitters.