在分层的铁电氧化二甲化物中操纵非线性光学反应
Liangting Ye1, Wenju Zhou2, Dajian Huang2
1Beijing Computational Science Research Center, Beijing, 100193, China.
Nature communications
|September 22, 2023
概括
范德瓦尔斯的氧化二甲化物表现出很大的非线性光学反应. 外部压力和光极化使可调节的光学特性成为可能,这对于先进的光电子设备至关重要.
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
- 光电学是指光电子产品.
背景情况:
- 可调节的非线性光学 (NLO) 响应对于光学和光电子设备至关重要.
- 范德瓦尔斯的氧化物二甲化物 (NbOX 2) 显示出显著的第二和生成 (SHG).
- 这些材料中NLO效应的起源和可调性需要进一步调查.
研究的目的:
- 研究NbOX2 (X = Cl, Br, I) 中大型SHG的物理起源.
- 探索NLO反应的可调性,包括NbOX2中的大量光伏 (BPV) 效应.
- 检查外部场 (应变,压力,光极化) 对NLO特性的影响.
主要方法:
- 分析电子带结构和嵌套效应的第一原则计算.
- 密度函数理论 (DFT) 用于研究光偏振依赖的轨道过渡.
- 在外部压力下对相位过渡和NLO反应的实验研究.
主要成果:
- 在NbOX2中的大型SHG部分归因于带嵌套效应.
- NbOCl 2显示了由光极化影响的明显的压力依赖的BPV效应.
- 在NbOCl2和NbOI2中,分别在压力下诱导了可逆的铁电到抗铁电和铁电到电相转换.
- 这些相位转换通过不同的微观机制导致可显著调节的NLO反应.
结论:
- 这项研究阐明了NbOX2材料中大型NLO反应背后的机制.
- 外界场,包括压力和光极化,为调整NLO属性提供了有效的路径.
- NbOX 2 材料显示了先进,可调节的非线性光学设备应用的潜力.
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