Comprehensive study of the ultrafast photoexcited carrier dynamics in Sb_(2)Te_(3)–GeTe superlattices  

作　　者：叶之江 金钻明 蒋叶昕 卢琦 贾梦辉 钱冬 黄夏敏 李舟 彭滟 朱亦鸣 Zhijiang Ye;Zuanming Jin;Yexin Jiang;Qi Lu;Menghui Jia;Dong Qian;Xiamin Huang;Zhou Li;Yan Peng;Yiming Zhu(Terahertz Technology Innovation Research Institute,Terahertz Spectrum and Imaging Technology Cooperative Innovation Center,Shanghai Key Laboratory of Modern Optical System,University of Shanghai for Science and Technology,Shanghai 200093,China;Shanghai Institute of Intelligent Science and Technology,Tongji University,Shanghai 200092,China;Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education),Shenyang National Laboratory for Materials Science,School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China;Tsung-Dao Lee Institute,Shanghai Jiao Tong University,Shanghai 200240,China;State Key Laboratory of Precision Spectroscopy,East China Normal University,Shanghai 200062,China;GBA Branch of Aerospace Information Research Institute,Chinese Academy of Sciences,Guangzhou 510700,China;Guangdong Provincial Key Laboratory of Terahertz Quantum Electromagnetics,Guangzhou 510700,China;University of Chinese Academy of Sciences,Beijing 100039,China)

机构地区：[1]Terahertz Technology Innovation Research Institute,Terahertz Spectrum and Imaging Technology Cooperative Innovation Center,Shanghai Key Laboratory of Modern Optical System,University of Shanghai for Science and Technology,Shanghai 200093,China [2]Shanghai Institute of Intelligent Science and Technology,Tongji University,Shanghai 200092,China [3]Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education),Shenyang National Laboratory for Materials Science,School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China [4]Tsung-Dao Lee Institute,Shanghai Jiao Tong University,Shanghai 200240,China [5]State Key Laboratory of Precision Spectroscopy,East China Normal University,Shanghai 200062,China [6]GBA Branch of Aerospace Information Research Institute,Chinese Academy of Sciences,Guangzhou 510700,China [7]Guangdong Provincial Key Laboratory of Terahertz Quantum Electromagnetics,Guangzhou 510700,China [8]University of Chinese Academy of Sciences,Beijing 100039,China

出　　处：《Chinese Physics B》2024年第7期381-387,共7页中国物理B（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(Grant Nos.2023YFF0719200 and 2022YFA1404004);the National Natural Science Foundation of China(Grant Nos.62322115,61988102,61975110,62335012,and 12074248);111 Project(Grant No.D18014);the Key Project supported by Science and Technology Commission Shanghai Municipality(Grant No.YDZX20193100004960);Science and Technology Commission of Shanghai Municipality(Grant Nos.22JC1400200 and 21S31907400);General Administration of Customs People’s Republic of China(Grant No.2019HK006)。

摘　　要：Chalcogenide superlattices Sb_(2)Te_(3)-GeTe is a candidate for interfacial phase-change memory(iPCM) data storage devices.By employing terahertz emission spectroscopy and the transient reflectance spectroscopy together,we investigate the ultrafast photoexcited carrier dynamics and current transients in Sb_(2)Te_(3)-GeTe superlattices.Sample orientation and excitation polarization dependences of the THz emission confirm that ultrafast thermo-electric,shift and injection currents contribute to the THz generation in Sb_(2)Te_(3)-GeTe superlattices.By decreasing the thickness and increasing the number of GeTe and Sb_(2)Te_(3) layer,the interlayer coupling can be enhanced,which significantly reduces the contribution from circular photo-galvanic effect(CPGE).A photo-induced bleaching in the transient reflectance spectroscopy probed in the range of~1100 nm to~1400 nm further demonstrates a gapped state resulting from the interlayer coupling.These demonstrates play an important role in the development of iPCM-based high-speed optoelectronic devices.

关 键 词：Sb_(2)Te_(3)/GeTe superlattices ultrafast carrier dynamics interfacial phase change memory THz emission spectroscopy transient reflectance spectroscopy 

分 类 号：O469[理学—凝聚态物理]