应变工程中Bi(111)薄膜的半导体-半金属转变及其机理

任师浩, 刘永利, 孟凡顺, 祁阳

Strain-Engineered Semiconductor to Semimetallic Transition and Its Mechanism in Bi(111) Film

REN Shihao, LIU Yongli, MENG Fanshun, QI Yang

图1 Bi晶体结构、薄膜结构示意图以及薄膜性质随厚度的变化

Fig.1 Hexagonal crystal structure (a, b, and c are lattice constants, a = b) (a), top and side views of 2 bilayers (BLs) atomic structure together (b), the optimized surface unit cell parameter as a function of the number of Bi BLs and experimental data[6] (c), the variation of intra-BL (d1) and inter-BL (d2) distances, as a function of the number of BLs (d), and calculated surface energy for free-standing Bi(111) films as a function of the number of BLs (e)