Division of Chemical Physics, Lund University , Box 124, 221 00 Lund, Sweden.
Department of Solid State Physics, Lund University , Box 118, 221 00 Lund, Sweden.
Nano Lett. 2015 Nov 11;15(11):7238-44. doi: 10.1021/acs.nanolett.5b02022. Epub 2015 Oct 9.
Measuring lifetime of photogenerated charges in semiconductor nanowires (NW) is important for understanding light-induced processes in these materials and is relevant for their photovoltaic and photodetector applications. In this paper, we investigate the dynamics of photogenerated charge carriers in a series of as-grown InP NW with different levels of sulfur (S) doping. We observe that photoluminescence (PL) decay time as well as integrated PL intensity decreases with increasing S doping. We attribute these observations to hole trapping with the trap density increased due to S-doping level followed by nonradiative recombination of trapped charges. This assignment is proven by observation of the trap saturation in three independent experiments: via excitation power and repetition rate PL lifetime dependencies and by PL pump-probe experiment.
测量半导体纳米线（NW）中光生电荷的寿命对于理解这些材料中的光诱导过程非常重要，并且与它们的光伏和光电探测器应用相关。在本文中，我们研究了一系列具有不同硫（S）掺杂水平的原生 InP NW 中光生载流子的动力学。我们观察到，随着 S 掺杂水平的增加，光致发光（PL）衰减时间以及积分 PL 强度都会降低。我们将这些观察结果归因于空穴的捕获，由于 S 掺杂水平导致的陷阱密度增加，随后是被捕获电荷的非辐射复合。这种分配通过三种独立实验中的观察得到证实：通过激发功率和重复率 PL 寿命依赖性以及 PL 泵浦探测实验。
