应变诱导对ZrSe2/HfSe2异构结构的光电子特性的影响
Xingbin Wei1, Lu Yang2, Shihang Sun1
1School of Architecture and Civil Engineering, Shenyang University of Technology, Shenyang, 110870, China.
Journal of molecular modeling
|December 11, 2023
概括
对ZrSe2/HfSe2异构结构施加应力,可以调节它们的光电子特性. 压缩应力将半导体转化为金属,而拉伸应变增强光吸收.
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:
- 二维 (2D) 半导体材料对于纳米光电子设备至关重要.
- 研究ZrSe2/HfSe2异构结构是因为它们的独特特性.
研究的目的:
- 研究施加应力对ZrSe2/HfSe2异构结构的电学和光学性能的影响.
- 探索应力工程在调节光电子特性方面的潜力.
主要方法:
- 使用密度函数理论 (DFT) 的第一原则计算与CASTEP模块.
- 施加压力和拉力应力范围从 -6%到 +6%到异构结构.
- 使用了超软的伪潜能,PBE-GGA交换相关函数和Monkhorst-Pack k点采样.
主要成果:
- 应力有效调节ZrSe2/HfSe2异质连接的带隙.
- 压缩应力通过关闭带隙导致半导体到金属的过渡.
- 拉伸应变会增加带隙,并将光吸收强度提高一个数量级 (10^4).
- 在不同的应力条件下观察到光学属性的红色或蓝色变化.
结论:
- ZrSe2/HfSe2异构结构具有显著的应力调节光电子特性.
- 这些异构结构对高性能光生成载体运输设备具有前景.
- 应力工程提供了一种强大的方法来为先进的应用量身定制材料特性.
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