摘要
The widespread application of photodetectors has triggered an urgent need for high-sensitivity and polarization-dependent photodetection.In this field,the two-dimensional(2D)tungsten disulfide(WS_(2))exhibits intriguing optical and electronic properties,making it an attractive photosensitive material for optoelectronic applications.However,the lack of an effective built-in electric field and photoconductive gain mechanism in 2D WS_(2)impedes its application in high-performance photodetectors.Herein,we propose a hybrid heterostructure photodetector that contains 1D Te and 2D WS_(2).In this device,1D Te induces in-plane strain in 2D WS_(2),which regulates the electronic structures of local WS_(2)and gives rise to type-Ⅱ band alignment in the horizontal direction.Moreover,the vertical heterojunction built of 2D WS_(2)and 1D Te introduces a high photoconductive gain.Benefiting from these two effects,the transfer of photogenerated carriers is optimized,and the proposed photodetector exhibits high sensitivity(photoresponsivity of ~27.7 A W^(-1),detectivity of 9.5×10^(12)Jones,and short rise/decay time of 19.3/17.6 ms).In addition,anisotropic photodetection characteristics with a dichroic ratio up to 2.1 are achieved.This hybrid 1D/2D heterostructure overcomes the inherent limitations of each material and realizes novel properties,opening up a new avenue towards constructing multifunctional optoelectronic devices.
随着光电探测器的广泛应用,人们迫切需要高灵敏度、偏振依赖的光电探测技术.在这一领域,二维二硫化钨(2D WS_(2))表现出出色的光学和电子特性,使其成为一种在光电应用领域有吸引力的光敏材料.但是,2D WS_(2)缺乏有效的内建电场和光电导增益机制,阻碍了其在高性能光电探测器中的应用.在此,我们提出了一种包含1D Te和2D WS_(2)的混合异质结构光电探测器.在该器件中,二维WS_(2)在1D Te上产生平面内形态应变,该应变能调节WS_(2)的局部电子结构,并在水平方向上形成II型能带排列.此外,2D WS_(2)和1D Te的垂直异质结引入了光电导增益.这两种效应优化了光致载流子的转移,使得光电探测器具有较高的灵敏度(光响应度为~27.7 A W^(-1),探测度为9.5×10^(12)Jones,上升/衰减时间为19.3/17.6 ms).此外,该器件还获得了各向异性的光电探测特性,其二向色比可达2.1.这种混合的1D/2D异质结构克服了单种材料固有的局限性,实现了新的性能,为构建多功能光电器件开辟了新的途径.
作者
Yuchen Zhou
Lixiang Han
Qiqi Song
Wei Gao
Mengmeng Yang
Zhaoqiang Zheng
Le Huang
Jiandong Yao
Jingbo Li
周瑜琛;韩理想;宋琦琦;高伟;杨孟孟;郑照强;黄乐;姚健东;李京波(Guangdong Provincial Key Laboratory of Information Photonics Technology,School of Materials and Energy,Guangdong University of Technology,Guangzhou 510006,China;Institute of Semiconductors,South China Normal University,Guangzhou 510631,China;State Key Laboratory of Optoelectronic Materials and Technologies,Nanotechnology Research Center,School of Materials Science&Engineering,Sun Yatsen University,Guangzhou 510275,China;Guangdong Provincial Key Laboratory of Chip and Integration Technology,Guangzhou 510631,China;State Key Laboratory for Superlattices and Microstructures,Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,China)
基金
supported by the National Natural Science Foundation of China(61805044,62004071 and 11674310)
the Key Platforms and Research Projects of Department of Education of Guangdong Province(2018KTSCX050)
Guangdong Provincial Key Laboratory of Information Photonics Technology(2020B121201011)
"The Pearl River Talent Recruitment Program"(2019ZT08X639)。
