能带调控对三元哈斯勒半金属材料TiIrBi结构和热电特性的影响  

The Effect of Band Regulation on the Eectronic Structure and Optical Properties of Half-Heusler Compound TiIrBi

作　　者：韦俊红 董宁 张敏平[2] WEI Junhong;DONG Ning;ZHANG Minping(School of Science,Henan Institute of Technology,Xinxiang 453003,China;School of Physics,Henan Normal University,Xinxiang 453007,China)

机构地区：[1]河南工学院理学部,河南新乡453003 [2]河南师范大学物理学院,河南新乡453007

出　　处：《河南工学院学报》2023年第1期24-30,共7页Journal of Henan Institute of Technology

摘　　要：采用第一性原理的方法,系统研究了外力调控下TiIrBi的电子结构以及热电特性。结果表明,TiIrBi是一种直接带隙的半导体材料,对其施加外力,在应变从-4%到4%的过程中,带隙减小,电子结构得到调控。当压缩应变ε=-1%时,TiIrBi的电子结构由直接带隙变化为间接带隙。施加压缩应变时,热电性能明显提高,热电优值达到0.96,n型掺杂影响显著。因此,压缩应变调控了TiIrBi的电子结构,提高了TiIrBi的热电性能。In this paper,the electronic structure and thermoelectric characteristics of TiIrBi under external control are systematically studied by using first-principles method.The results show that TiIrBi is a semiconductor material with a direct band gap.The band gap decreases and the electronic structure is regulated when the strain is applied from-4%to 4%.When the strain is compressedε=-1%,the electronic structure of TiIrBi changes from direct band gap to indirect band gap.When the compression strain is added,the thermoelectric performance is improved obviously,and the thermoelectric optimum value reaches 0.96.Therefore,compressive strain regulates the electronic structure of TiIrBi and improves the thermoelectric properties of TiIrBi.

关 键 词：电子结构 热电性质 外力 第一性原理计算 

分 类 号：O469[理学—凝聚态物理]