原子与分子物理学报2013，Vol.30Issue(3)：471-478,8.DOI:10.3969/j.issn.1000-0364.2013.03.022
掺杂BaHfO3电子结构与力学性能的第一性原理研究
First-principles study of electronic structure and mechanical characteristics of doping BaHfO3
摘要
Abstract
The influences of doping on electronic structures and mechanical properties of BaHfO3 are investigated by using first-principles plane-wave density functional theory within the generalized gradient approximation (GGA).The electronic structure calculations show that the lattice constant of optimized BaHfO3 agrees with the experimental value,and BaHfO3 and doped BaHfO3 with Sr or Ti are both indirect band gap materials.Specifically,the band gap of Ba0.5Sr0.5HfO3 increases and the characteristics of insulator enhances,while the band gap of BaHf0.5Ti0.5O3 is obviously reduced and the features of semiconductor material are displayed.The analysis of the density of states shows that the change of the band gap after doping is due mainly to the movement of the bottom of conduction band.The analysis of mechanical properties indicates that the shear modulus and Young's modulus of Ba0.5 Sr0.5 HfO3 decrease comparing with BaHfO3,which leads to the decrease of the hardness of the material.But for BaHf0.5Ti0.5O3,both the shear modulus and Young's modulus increase,which causes the enhance of hardness.Electron density distribution analysis reveals that the doping changes the valence electron concentration distribution of the system,resulting in the change of bonding characteristics of BaHfO3,and this is the underlying reason for the change of hardness of the material.Thus,the doping can effectively control the hardness of the system.The results of the study provide a theoretical basis for the design and application of doping BaHfO3 electromechanical materials.关键词
BaHfO3/第一性原理/电子结构/力学性质/掺杂Key words
BaHfO3/ first principles/ electronic structure/ mechanical properties/ doping分类
数理科学引用本文复制引用
张加宏,杨镇博,顾芳,刘清惓,冒晓莉,李敏..掺杂BaHfO3电子结构与力学性能的第一性原理研究[J].原子与分子物理学报,2013,30(3):471-478,8.基金项目
国家自然科学基金(41075026) （41075026）
江苏省自然科学基金(BK2012460) （BK2012460）
东南大学MEMS教育部重点实验室开放研究基金(2010-02) （2010-02）
南京信息工程大学校预研基金(20110369) （20110369）
