【摘要】 利用基于密度泛函理论的第一性原理平面波赝势方法分别计算了本征及过渡金属掺杂单层MoS₂的晶格参数、电子结构和光学性质。计算结果显示,过渡金属掺杂所引起的晶格畸变与杂质原子的共价半径有联系,但并不完全取决于共价半径的大小。分析能带结构可以看到,Co、Ni、Cu、Tc、Re和W掺杂使能带从直接带隙变成了间接带隙。除了Cr和W以外,其它掺杂体系的禁带区域都出现了数目不等的新能级,这些杂质能级主要由杂质的d、S的3p和Mo的4d轨道组成。掺杂对MoS₂的光学性质也产生了相应的影响,使MoS₂的静态介电常数、介电函数虚部峰值、折射率和光电导率峰值呈现不同程度的增加。更多还原

【Abstract】 The effect of transition metal doping on electronic structure and optical properties of monolayer MoS₂ is conducted by using the plane-wave pseudopotential density functional theory method.Calculations indicate that lattice distortion in doped monolayer MoS₂ is relative to the magnitude of the covalent radius of doping atom.Analysis of band structure shows that Co,Ni,Cu,Tc,Re and W doping make the transition of energy band structure change from direct to indirect.Besides Cr and W,other doping system induce different number energy levels in the forbidden band of MoS₂,and these impurity levels are composed mainly by doping atom-d,S3 p and Mo4 d.The doping has also changed the optical properties of monolayer MoS₂.The static dielectric constant,imaginary part peak of dielectric function,refractive index and conductivity peak are increased with various degrees.更多还原