光抽运太赫兹探测技术研究ZnSe的光致载流子动力学特性

发布时间：2018-03-06 03:16

本文选题：光抽运-太赫兹探测　切入点：光密度　出处：《物理学报》2016年24期 　论文类型：期刊论文

【摘要】：利用光抽运-太赫兹探测技术,研究了ZnSe的载流子弛豫过程和太赫兹波段电导率的时间演化过程.在中心波长为400 nm的抽运光作用下,ZnSe的载流子弛豫过程用双指数函数进行了很好的拟合,其快的载流子弛豫时间和慢的载流子弛豫时间均随抽运光密度的增加而增大.快的载流子弛豫时间随抽运光密度的增加而增大与样品中的缺陷有关,随着激发光密度的增加,激发的光生载流子浓度增大,缺陷逐渐被光生载流子填满,致使快的载流子弛豫时间增大;慢的载流子弛豫时间随着抽运光密度增加而增大主要和带填充有关.不同抽运光延迟时间下ZnSe在太赫兹波段的瞬态电导率用Drude-Smith模型进行了很好的拟合.对ZnSe光致载流子动力学特性的研究为高速光电器件的设计和制造提供了重要的实验依据.
[Abstract]:Using optically pumped terahertz detection technology, The carrier relaxation process of ZnSe and the time evolution process of THz conductivity are studied. The carrier relaxation process of ZnSe is well fitted by double exponential function under the action of the pump light at the central wavelength of 400nm. Both the fast carrier relaxation time and the slow carrier relaxation time increase with the increase of the pump optical density. The increase of the fast carrier relaxation time is related to the defects in the sample, and with the increase of the excited optical density, the fast carrier relaxation time increases with the increase of the pump optical density. When the concentration of photoinduced carriers increases, the defects are gradually filled with photocarriers, which results in the increase of fast carrier relaxation time. The increase of slow carrier relaxation time with the increase of pump density is mainly related to band filling. The transient conductivity of ZnSe at terahertz band at different pump delay times is well fitted by Drude-Smith model. ZnSe photoluminescence is obtained. The study of carrier dynamics provides an important experimental basis for the design and manufacture of high-speed optoelectronic devices.
【作者单位】：上海电力学院电子与信息工程学院;中国科学院上海技术物理研究所中国科学院红外物理国家重点实验室;上海大学物理系;山东师范大学物理与电子科学学院;
【基金】：国家自然科学基金(批准号:11404207,11674213) 上海市自然科学基金(批准号:14ZR1417500) 上海市科委地方院校能力建设项目(批准号:15110500900,14110500900) 上海市教委科研创新项目(批准号:15ZZ086) 上海市教委高校青年教师培养资助项目(批准号:ZZsdl15106) 上海电力学院人才引进基金(批准号:K2014-028)资助的课题~~
【分类号】：O472;O441.4

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