本研究建立了纤铁矿TiO2和GaSe二维晶体的物理模型,用第一性原理的密度泛函方法计算了两体系的能带性质,分析了体系的电子态及光谱性质,并进一步研究了二轴张力对体系的能带的调控作用,最后分析了二轴张力对体系电子态性质和光谱性质的调控作用。结果表明,通过二轴张力,可以有效地调节两体系的带隙宽度,进而调节两体系的光谱响应特性,从而拓展了二维晶体在可控电子学、光伏器件等领域的应用。

In this paper,a physical model of lepidocrocite-TiO2 and GaSe 2D crystals are established.The calculation of the band structure,density of states and optical spectrums of these crystals are performed with the first-principles density functional theory(DFT).The influence of the biaxial stress to the band structure and optical response of the 2D crystals are calculated.The results show that the band gap can be tuned systematically via the biaxial stress.There is a.This study paves the path for these 2D crystals′ further application in tunable electronic devices and photovoltaic devices.