连续体中的边界状态在被分割的三角孔元表面中
1Institute of Applied Mechanics, National Taiwan University, Taipei, 106, Taiwan. chernrl@ntu.edu.tw.
Scientific reports
|June 6, 2024
概括
在介电元表面的连续性 (BIC) 中的边界状态可以通过调整几何参数来生成,分割和合并. 这项研究探讨了三角孔元面中的BIC操纵,揭示了拓电荷过渡.
科学领域:
- 光子学和元材料研究
- 光学物理学的光学物理学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 连续性的边界状态 (BIC) 是具有无限质量因子的独特光学状态.
- 超表面提供了多功能平台,可以在纳米尺度上操纵光.
- 了解BIC行为对于先进的光学设备设计至关重要.
研究的目的:
- 研究介电元表面中BICs的生成,分裂和合并动态.
- 分析与BICs相关的拓性质和极化奇点.
- 探索几何参数,特别是高度比在控制BIC现象中的作用.
主要方法:
- 介电元面的数值模拟,在正方形格子中具有分割的三角孔.
- 分析分散带和质量因素以确定BIC.
- 极化奇点 (V点和C点) 的表征及其拓电荷.
主要成果:
- 一个具有很大的质量因子的偶然BIC在Brillouin区域中心出现,被确定为具有整数拓电荷的V点.
- 随着高度比率的增加,BIC分裂成两个循环极化状态 (C点),具有半整数拓电荷.
- 这些状态合并为另一个V点BIC,被确定为弗里德里希-温特根BIC,靠近一个避免过境.
结论:
- 对BIC生成,分裂和合并的几何控制在介电元面中得到了证明.
- 该研究揭示了几何参数,BIC拓电荷和极化奇点之间的直接相关性.
- 这些发现为BIC的基本物理及其在光学设备中的潜在应用提供了洞察力.
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