文献类型：期刊文献

英文题名：Ultrafast optical modulation of terahertz metamaterials

作者：Zhou, Qingli[1];Shi, Yulei[1];Wang, Aihua[1];Li, Lei[1];Zhao, Dongmei[1];Liu, Jianfeng[1];Sun, Huijuan[2];Zhang, Cunlin[1]

第一作者：Zhou, Qingli

通讯作者：Zhou, QL[1]

机构：[1]Capital Normal Univ, Beijing Key Lab Terahertz Spect & Imaging, Key Lab Terahertz Optoelect, Minist Educ,Dept Phys, Beijing 100048, Peoples R China;[2]Beijing Union Univ, Dept Basic Course, Beijing 100101, Peoples R China

第一机构：Capital Normal Univ, Beijing Key Lab Terahertz Spect & Imaging, Key Lab Terahertz Optoelect, Minist Educ,Dept Phys, Beijing 100048, Peoples R China

通讯机构：[1]corresponding author), Capital Normal Univ, Beijing Key Lab Terahertz Spect & Imaging, Key Lab Terahertz Optoelect, Minist Educ,Dept Phys, Beijing 100048, Peoples R China.

年份：2011

卷号：13

期号：12

外文期刊名：JOURNAL OF OPTICS

收录：;EI(收录号：20115114628593);Scopus(收录号：2-s2.0-83755183052);WOS:【SCI-EXPANDED(收录号:WOS:000298412400003)】；

基金：This work was funded by the National Keystone Basic Research Program (973 Program) under grant No. 2007CB310408, the National Natural Science Foundation of China under grant Nos 10804077, 10904098, and 11011120242, Beijing Municipal Commission of Education under grant No. KM200910028006, Ministry of Education key project under grant No. 210002, the Beijing Nova Program, and the Funding Project for Academic Human Resources Development in Institutions of Higher Learning Under the Jurisdiction of Beijing Municipality.

语种：英文

外文关键词：terahertz; spectroscopy; split ring resonator

摘要：We have characterized the ultrafast dynamical properties of split ring resonators by utilizing optical pump-terahertz probe spectroscopy on a subpicosecond timescale. The experimental results show that the pump-induced relative changes in terahertz peak transmission, as well as the dynamical transmission spectra, are different when the terahertz electric vector is perpendicular and parallel to the gap of the split ring resonator. It is found that the pump-induced photogenerated carriers play two opposite roles in SRRs, showing one is to absorb terahertz to reduce the transmission in the substrate and the other is to weaken the resonant absorption to enhance the transmission. Our numerical simulations also prove that the pump pulse significantly influences the split ring resonator currents. We also show that the blue-shifts of the resonances are due to the change of optical constants in the photoexcited semiconductor substrate.