标题:
具有氧缺陷的SrTiO3的电子结构和光学性质的第一性原理研究Electronic Structures and Optical Properties of the Oxygen-Deficient SrTiO3 from First-Principles Calculation
作者:
陈清源, 何垚
关键字:
第一性原理计算, SrTiO3, 缺陷, 电子结构, 光学性质First-Principles Calculation, SrTiO3, Defect, Electronic Structure, Optical Properties
期刊名称:
《Modern Physics》, Vol.4 No.5, 2014-09-24
摘要:
近年来,钙钛矿型氧化物由于其具有独特的结构以及丰富的物理化学性质而受到广泛的关注。SrTiO3(以下简称STO)是一种典型钙钛矿型氧化物,具有典型钙钛矿结构所具有的特点,并且其较高的介电常数、低介电损耗及良好的热稳定性使其备受关注。本文针对其结构特性及光学性质运用了第一性原理进行了研究,发现运用LDA + U方法能够更准确地描述其电子结构,获得与实验值更加吻合的禁带宽度。在这基础上,我们能够准确地预言,通过氧缺陷能够引入缺陷态,并在吸收谱中引入新的吸收带,实现对可见光的有效利用。In recent years, perovskite oxides attracted widely attention due to its unique structure and the chemical and physical properties. SrTiO3 (hereinafter referred to STO) is a kind of typical perovskite oxides. It has the characteristics of typical perovskite structure, and its high dielectric constant, low dielectric loss and good thermal stability made it easier to attract more attentions. In this paper, we investigate the electronic and optical properties of STO using LDA + U method. We found that this method predicts more accurate band gap for STO. The oxygen vacancy induced local defect state and new absorption band, which enhanced the efficiency of absorption in the visible region.