纤锌矿Be_xZn_(1-x)O合金能隙弯曲系数的第一原理研究  

First-principles study on the energy bandgap bowing parameter of wurtzite Be_xZn_(1-x)O

作　　者：郑树文[1] 范广涵[1] 张涛[1] 苏晨[1] 宋晶晶[1] 丁彬彬[1] 

机构地区：[1]华南师范大学,光电子材料与技术研究所,广州510631

出　　处：《物理学报》2013年第3期297-303,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61176043);广东省战略性新兴产业专项资金(批准号:2010A081002005;2011A081301003;2012A080304016;2012A080304016);广东省教育部产学研结合项目(批准号:2010B090400192)资助~~

摘　　要：采用密度泛函理论框架下的第一性原理平面波超软赝势方法,对纤锌矿BexZn1-xO合金进行能隙特性、弯曲系数和结构参数的计算.结果表明:BexZn(1-x)O合金的能隙和弯曲系数都随Be掺杂组分的增大而增大.通过修正BexZn(1-x)O合金的能隙值得知其合金弯曲系数b为6.02eV,这与实验值接近.纤锌矿BexZn(1-x)O合金的能隙弯曲系数过大主要来源于体积形变和电荷转移的贡献.文中还分析了BexZn(1-x)O合金的晶格常数、平均键长和平均次近邻原子距离与Be组分的关系.First-principles plan-wave pseudopotential method is used to calculate the energy bandgap properties, bowing parameters and structural properties of wurtzite BexZn1-xO alloys. The results show that the energy bandgaps and bowing parameters of BexZn1？xO alloys increase with Be content increasing. We find the energy bandgaps corrected of BexZn1-xO alloys to be in accordance with the experimental value. The reason about the energy bandgap broadening is also analyzed. The average bowing parameter of BexZn1-xO alloys is 6.02 eV, which is in good agreement with previous experimental result. The bowing parameter mostly arises from volume deformation of alloy and charge transfer effect. Futhermore, we analyze the changes of lattice parameter, average bond length and average second-neighboring distance with Be content in BexZn1？xO alloys.

关 键 词：第一性原理 BexZn1-xO 能隙 弯曲系数 

分 类 号：O469[理学—凝聚态物理]