用密度函数理论和光谱圆测量来开发纯净和W-Doped VO薄膜的分析程序和分散模型2
Benedict S Morris1,2, Zahra Shayegan1, Daniel Koch1
1Institut National de la Recherche Scientifique Centre Énergie Matériaux et Télécommunications, 1650 Boulevard Lionel-Boulet, Varennes J3X 1P7, Canada.
ACS applied materials & interfaces
|December 2, 2024
概括
一种新的方法可以准确地确定二氧化瓦纳 (VO2) 薄膜的光学特性. 这项分析显示, (W) 兴奋剂主要影响VO2.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术 纳米技术
背景情况:
- 二氧化瓦纳 (VO2) 在室温附近呈现半导体到金属相位过渡,这对于智能材料至关重要.
- VO2的光学特性对合成方法和兴奋剂非常敏感,需要准确的表征.
- (W) 兴奋剂降低了过渡温度,影响了VO2在先进技术中的效用.
研究的目的:
- 为准确确定原始VO2薄膜的光学特性提出一种通用分析程序.
- 使用密度函数理论开发VO2的新型分散模型.
- 调查W-doping对VO2光学特性的影响.
主要方法:
- 使用密度函数理论开发VO2特异性分散模型.
- 应用分散模型来分析原始和W-doped VO2薄膜的光学特性.
- 低于和高于过渡温度的光学吸收光谱的比较.
主要成果:
- 开发的分散模型准确地描述了2到5 eV之间的VO2光学吸收的四个贡献.
- 该分析程序使用文献数据进行了验证,并成功地应用于W-doped VO2 电影.
- 在低温阶段,W-doping主要影响近红外光学特性,增加了低于1 eV的吸收.
结论:
- 已经建立了一个强大的方法来表征VO2光学特性.
- 该研究提供了原始和W-doped VO2 光学性能的直接比较.
- W-doping显著改变了VO2的光学吸收边缘和近红外响应.
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