Isotropic or anisotropic screening in black phosphorous: Can doping tip the balance?  

作　　者：Zhi-Min Liu Ye Yang Yue Shao Zheng Qin-Jun Chen Ye-Xin Feng 

机构地区：[1]Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics&Devices,School of Physics and Electronics,Hunan University,Changsha,410082,China

出　　处：《Frontiers of physics》2020年第5期103-109,共7页物理学前沿（英文版）

基　　金：Y.X.Feng was supported by the National Basic Research Programs of China with grant No.2016YFA0300901;the National Natural Science Foundation of China with grant Nos.11974105 and 11634001.

摘　　要：Black phosphorus(BP),a layered van der Waals(vdW)crystal,has umique in-plane band anisotropy and many resulting anisotropy properties such as the ffective mass,electron mobility,optical absorp-tion,thermal conductivity and plasmonie dispersion.However,whether anisotropic or isotropic charge screening exist in BP remains a controversial sse.Based on first-principles calculations,we study the screening properties in both of single-layer and bulk BP,especially conoerning the role of doping.Without charge doping,the single-layer and bulk phase BP show slight anisotropic screening.Electron and hole doping can increase the charge screening of BP and significantly change the relative static dielectric tensor elements along two different in-plane directions.We further study the charge density change induced by potassium(K)adatom near the BP surface,under different levels of charge dop-ing.The calculated two-dimensional(2D)charge redlistribution patterns also confirm that doping can greatly ffect the screening feature and tip the balance between isotropic and anisotropice screening.We corroborate that screening in BP exhibits slight intrinsic anisotropy and doping has significant influenoe on its screening property.

关 键 词：first-principles calculation charge screening black phosphorus dielectric function DOPING 

分 类 号：O48[理学—固体物理]