Controlling electronic structures by irradiation in single-walled SiC nanotubes: a first-principles molecular dynamics study

Using first-principles molecular dynamics simulations, the displacement threshold energy and defect configurations are determined in SiC nanotubes. The simulation results reveal that a rich variety of defect structures (vacancies, Stone-Wales defects and antisite defects) are formed with threshold energies from 11 to 64 eV. The threshold energy shows an anisotropic behavior and exhibits a dramatic decrease with decreasing tube diameter. The electronic structure can be altered by the defects formed by irradiation, which suggests that the electron irradiation may be a way to use defect engineering to tailor electronic properties of SiC nanotubes.

National Natural Science Foundation of China 10704014 Young Scientists Foundation of UESTC JX0731 Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, US Department of Energy DE-AC05-76RL01830 Chinese Academy of Sciences ZW was financially supported by the National Natural Science Foundation of China (10704014) and the Young Scientists Foundation of UESTC (JX0731). Two authors (FG and WJW) were supported by the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, US Department of Energy under contract DE-AC05-76RL01830. JL gratefully acknowledges financial support from the 'One-Hundred Talents Plan' of the Chinese Academy of Sciences.