Black phosphorus (BP), a layered van der Waals (vdW) crystal, has unique in-plane band anisotropy and many resulting anisotropy properties such as the effective mass, electron mobility, optical absorption, thermal conductivity and plasmonic dispersion. However, whether anisotropic or isotropic charge screening exist in BP remains a controversial issue. Based on first-principles calculations, we study the screening properties in both of single-layer and bulk BP, especially concerning 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 doping. The calculated two-dimensional (2D) charge redistribution patterns also confirm that doping can greatly affect the screening feature and tip the balance between isotropic and anisotropic screening. We corroborate that screening in BP exhibits slight intrinsic anisotropy and doping has significant influence on its screening property.

黑磷（BP）是层状范德华（vdW）晶体，具有独特的面内各向异性，并且具有许多各向异性特性，例如有效质量，电子迁移率，光吸收，热导率和等离子体分散。但是，BP中是否存在各向异性或各向同性的电荷筛选仍然是一个有争议的问题。基于第一性原理计算，我们研究了单层和块状BP的筛选特性，特别是关于掺杂的作用。如果不进行电荷掺杂，则单层和体相BP表现出轻微的各向异性筛选。电子和空穴掺杂可以增加BP的电荷屏蔽，并沿两个不同的面内方向显着改变相对静态介电张量元素。我们进一步研究了在不同水平的电荷掺杂下，BP表面附近的钾（K）原子诱导的电荷密度变化。计算得出的二维（2D）电荷再分布模式还证实，掺杂会极大地影响筛选功能，并在各向同性和各向异性筛选之间取得平衡。我们证实了在BP中的筛选表现出轻微的固有各向异性，并且掺杂对其筛选性能具有重大影响。