半导体纳米颗粒载流子的超快弛豫过程

J4 ›› 2010, Vol. 27 ›› Issue (5): 607-612.

半导体纳米颗粒载流子的超快弛豫过程

黄曙亮, 梁瑞生, 陈振宇, 廖浩祥

华南师范大学信息光电子科技学院光子信息技术广东省高校重点实验室，广东广州 510006

收稿日期:2009-10-29 修回日期:2009-12-14 出版日期:2010-09-28 发布日期:2010-08-31
通讯作者: 梁瑞生教授，硕士生导师，现任中国物理学会光物理专业委员会副主任，广东省光学学会副理事长、广州光学学会理事长。 E-mail:liangrs@scnu.edu.cn
作者简介:黄曙亮研究生，主要从事微纳米光学材料的研究。 E-mail: hsl2000@126.com
基金资助:
国家重点基础研究发展计划973项目（2007CB307002）资助

Ultrafast relaxation process of photoexcited charge carriers in semiconductor nanoparticles

HUANG Shuliang, LIANG Ruisheng, CHEN Zhenyu, LIAO Haoxiang

Laboratory of Photonic Information Technology, School for Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, China

Received:2009-10-29 Revised:2009-12-14 Published:2010-09-28 Online:2010-08-31

摘要/Abstract

摘要：

分析了纳米颗粒的能级结构，建立了载流子弛豫的简化模型，运用数值模拟方法讨论了激发密度、表面态密度及俘获态电子的弛豫率对弛豫过程的影响。讨论结果表明，激发密度的增大及表面态的减少都会导致表面态上电子的饱和，使导带上出现电子的积累，导带电子寿命增大；深俘获态电子的弛豫是影响材料响应速度的主要因素。最后应用此模型对近红外泵浦探测实验的结果进行分析，表明模型可望在实验结果分析上得到应用。

关键词: 半导体纳米颗粒, 超快载流子弛豫, 速率方程, 泵浦探测

Abstract:

Ultrafast relaxation process of photoexcited charge carriers in semiconductor nanoparticles is modeled with the analysis of state levels structure.　Then, several parameters, that would affect this process, are discussed. The result shows that, with the increasing of excited intensity or the decreasing of surface state density, the electron saturation of the surface state would causes the electron build-up of conduction state and leads to a longer life time; the relaxation of deep trapped electrons is the main limit of response time for nanoparticles. At last, this model is used to analyze pump-probe experiment,　showing potential use in experimental analysis.

Key words: semiconductor nanoparticle, ultrafast carrier relaxation, rate equation, pump-probe

黄曙亮梁瑞生陈振宇廖浩祥. 半导体纳米颗粒载流子的超快弛豫过程[J]. J4, 2010, 27(5): 607-612.

HUANG Shuliang LIANG Ruisheng, CHEN Zhenyu LIAO Haoxiang. Ultrafast relaxation process of photoexcited charge carriers in semiconductor nanoparticles[J]. J4, 2010, 27(5): 607-612.

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