在ZnxCd1-xTe超网中通过可变原子排序进行带隙调整
V Barone1, R J Ellingson1, S V Khare1
1Department of Physics, Wright Center for Photovoltaics Innovation and Commercialization, University of Toledo, Toledo, Ohio 43606, USA.
The Journal of chemical physics
|August 12, 2024
概括
ZnxCd1-xTe超级格子的堆叠顺序显著影响它们的带隙,其变化高达0.2 eV. 这一发现对于为先进应用调整半导体特性至关重要.
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
- 固态化学 固态化学
背景情况:
- 超级网格提供可调节的电子和光学特性.
- ZnxCd1-xTe合金是有前途的半导体材料.
- 了解超级格子中的结构属性关系是材料设计的关键.
研究的目的:
- 为了探索32层ZnxCd1-xTe超级格子的完整结构配置空间.
- 为了确定最小化和最大化所有度的带隙的结构.
- 调查堆叠顺序对物理性质的影响.
主要方法:
- 利用价值力场动力学,经验性伪潜力方法和折叠频谱方法进行结构性搜索.
- 用密度函数理论与混合函数来进行属性计算.
- 开发了一种替代的先决条件,以提高局部最佳的先决条件结合梯度方法的效率.
主要成果:
- 发现ZnxCd1-xTe超级格子的带隙因堆叠顺序而变化高达0.2 eV.
- 计算了形成能量,带隙,状态密度,有效质量和光学响应函数.
- 计算的属性与现有的实验数据有很好的一致性.
- 堆叠顺序显著影响有效质量不规则,而光学特性在很大程度上保持不敏感.
结论:
- 堆叠序列是控制ZnxCd1-xTe超格子中带隙的一个关键参数.
- 这些发现为这些材料的精确带隙工程提供了一条途径.
- 这项工作促进了对光电子应用纳米级材料设计的理解.
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