Recombination dynamics of excitons and biexcitons in a hexagonal GaN epitaxial layer
Recombination dynamics of excitons and biexcitons in a hexagonal GaN epitaxial layer
复制标题
六方氮化镓外延层中激子和双激子的复合动力学
DOI：
10.1063/1.117599
复制
发表时间：
1996
影响因子：
4
通讯作者：
S. Nakamura
中科院分区：
文献类型：
--
作者：
Y. Kawakami;Z. Peng;Y. Narukawa;S. Fujita;S. Fujita;S. Nakamura
在 18 K 下对双流金属有机化学气相沉积 (TF-MOCVD) 生长的无意掺杂的六方 GaN 外延层中的激子相关发射进行了时间分辨光致发光 (PL) 光谱分析。在低激发条件下，A自由激子（EXA：3.4921 eV）和中性浅受体束缚激子[（A0s，X）：3.4805 eV]的辐射复合主导了光谱。 (A0s,X) 发射的衰减时间相对较长 (585 ps)，表明该层中存在少量非辐射中心。在较高的激发密度下，新的 PL 峰出现在 3.4864 eV 处，并随激发密度超线性增长。这些特征与它们的瞬态行为相结合，表明这个新的发射带是由于双激子复合造成的。
Time‐resolved photoluminescence (PL) spectroscopy has been performed at 18 K on excitonic‐related emissions in an unintentionally doped hexagonal GaN epitaxial layer grown by two‐flow metalorganic chemical vapor deposition (TF‐MOCVD). Under low excitation condition, radiative recombination of A free exciton (EXA: 3.4921 eV) and neutral shallow‐acceptor bound exciton [(A0s,X): 3.4805 eV] dominated the spectrum. Decay time of (A0s,X) emission is relatively long (585 ps) indicating a small number of non‐radiative centers in the layer. At higher excitation densities, new PL peak appeared at 3.4864 eV and grew superlinearly with excitation densities. These features, combined with their transient behavior, suggest that this new emission band is due to the biexciton recombination.