Lu2O3晶体在高压下的光学性质第一性原理研究

Optical properties of Lu2O3 at high pressure:a first principles study

本文采用第一性原理方法,计算了Lu2O3(氧化镥)的理想晶体和含氧、镥空位点缺陷晶体在100 GPa压力范围内的光吸收谱和折射率性质.结果表明:在100 GPa范围内,Lu2O3理想晶体在可见光及红外光区不具有光吸收现象,空位点缺陷的存在将导致吸收边红移,其中氧空位点缺陷引起的红移行为更显著,但这些吸收边仍未进入可见光区的高波段.532 nm处的折射率数据表明,在立方结构和单斜结构相区,Lu2O3晶体的折射率随压力的增加而增大,高压结构相变以及氧、镥空位的存在也会使得折射率增大.结合温度效应分析推测,Lu2O3晶体在近红外区有可能透明.

The optical properties of Lu2O3 crystal with and without V0+2 and VLu-3 vacancy defects within pressure 100 GPa were calculated using the first-principles method.The results show that,within 100 GPa,there is no light absorption in visible and infrared region for perfect Lu2O3.The presence of vacancy defect will cause its absorption edge redshift.Among them,V0+2 causes the more obvious red-shift behavior,but there was still no light absorption in the high-wavelength range of the visible region.The refractive-index data at 532 nm indicate that the Lu2O3 refractive indexes in cubic and monoclinic regions enhance with increasing pressure,and its high-pressure structural transition and the presence of V0+2 or VLu-3 also cause an enhancement in refractive index,respectively.An analysis,together with temperature effects,suggests that the Lu2O3 crystal is transparent in near-infrared region.