在迪拉克半金属元表面的连续体中以对称性保护的极化敏感束状态:对折射率传感的比较研究和应用
Optics express
|August 13, 2025
概括
这项研究引入了一个可调节的超表面,使用迪拉克半金属来对偏振敏感光进行操纵. 它展示了高的Q因子和传感能力,为先进的危险检测和生物医学诊断铺平了道路.
科学领域:
- 地元表面光学学
- 凝聚物质物理学 凝聚物质物理学
- 纳米光子学 纳米光子学
背景情况:
- 超表面提供了对电磁波的多功能控制.
- 迪拉克半金属 (DS) 具有独特的电子特性,适用于可调节设备.
- 连续体中的边界状态 (BIC) 提供高Q共振,但主动调具有挑战性.
研究的目的:
- 设计和研究一个可主动调节的,极化敏感的准BIC元表面.
- 探索BIC到准BIC转换的对称性破坏方法.
- 为了展示超表面对于感知应用的潜力.
主要方法:
- 在SiO2基板上制造一个由三条DS条组成的超表面.
- 对三种破坏对称性的技术进行比较分析.
- 准BIC状态,Q因子,电场分布,表面电流密度和多极分解的表征.
- 通过调整DS条的费米能量来主动调整共振频率.
- 使用具有不同折射率的分析物进行传感测量.
主要成果:
- 达到7624的最大Q因子.
- 已确认的准BIC状态主要来自电偶极振荡.
- 通过调整费米能量,通过1.802-1.826 THz (x-pol) 和1.259-1.284 THz (y-pol) 的共振频率进行了积极调整.
- 获得的传感灵敏度高达0.406 THz/RIU和FOM为418.8 RI-1 (x-pol),以及0.267 THz/RIU和232.6 RI-1 (y-pol).
结论:
- 设计的超表面能够进行主动调整和对准BIC状态的极化敏感控制.
- 该设备在太赫兹应用中具有显著的高性能传感潜力.
- 这项工作有助于开发先进的电磁波操纵和传感技术.
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