Doppler 程序对金红石型 TiO2的空位缺陷研究

摘要

Rutile TiO2 is a good dilute magnetic semiconductor material.Its magnetism is closely related to the intrinsic defects.In this paper , Doppler program based on the generalized gradient theory ( GGA) is used to cal-culate the positron annihilation lifetimes of different defects , including the annihilation lifetimes of freedom elec-tron states and annihilation lifetimes of different types of vacancies ( single slot and double slot ) , in bulk rutile TiO2.Furthermore, Doppler broadening spectra of rutile TiO 2 containing vacancy defects are given theoretically.%金红石型TiO2是一种非常好的稀磁半导体材料，其自身的本征缺陷与室温铁磁性起源密切相关。本文利用Doppler程序在广义梯度理论（ GGA）的基础上，计算了正电子在金红石型TiO2块材中不同缺陷处的湮没寿命。主要包括自由态正电子的湮没寿命，单空位和双空位处束缚态正电子的湮没寿命。并从理论上给出了含有空位缺陷时金红石型TiO2的符合多普勒展宽能谱。