Double topological phase singularities in highly absorbing ultra-thin film structures for ultrasensitive humidity sensing
用于超灵敏湿度传感的高吸收超薄膜结构中的双拓扑相位奇异性
超感度湿度センシング用の高吸収超薄膜構造におけるデュアルトポロジー位相特異性
초민감 습도 감지에 사용되는 고흡수 초박막 구조에서의 이중 토폴로지 위상 기이성
Singularidades de fase de doble papá en estructuras de película ultrafina de alta absorción para sensores de humedad ultrasensibles
Singularité de phase à double topologie dans les structures à membrane ultramince à haute absorption pour la détection ultra - sensible de l'humidité
Двойная топологическая фазовая сингулярность в высокоабсорбционной сверхтонкой мембранной структуре
Xiaowen Li 李晓温 ¹ ², Jie Sheng ², Zhengji Wen 文政绩 ³, Fangyuan Li ², Xiran Huang ², Mingqing Zhang ¹, Yi Zhang ², Duo Cao ², Xi Shi 石溪 ², Feng Liu 刘锋 ², Jiaming Hao 郝加明 ¹
¹ Institute of Optoelectronics & Department of Materials Science, Shanghai Frontiers Science Research Base of Intelligent Optoelectronics and Perception, Fudan University, Shanghai 200433, China
中国 上海 复旦大学 光电研究院 材料科学系 上海市智能光电与感知前沿科学研究基地
² Department of Physics, Shanghai Normal University, Shanghai 200234, China
中国 上海 上海师范大学物理系
³ State Key Laboratory of Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
中国 上海 中国科学院上海技术物理研究所 红外物理国家重点实验室
Phase singularities (PSs) in topological darkness-based sensors have received significant attention in optical sensing due to their rapid, ultra-sensitive, and label-free detection capabilities. Here, we present both experimental and theoretical investigations of an ultrasensitive and multiplexed phase-sensitive sensor utilizing dual topological PSs in the visible and near-infrared regions.
This sensor uses a simple structure, which consists of an ultra-thin highly absorbing film deposited on a metal substrate. We demonstrate the achievement of dual-polarization darkness points for s- and p-polarizations at different incident angles. Furthermore, we theoretically explain the double topological PSs accompanied by a perfect ±π-jump near a zero-reflection point, based on the temporal coupled-mode formalism.
To validate its multifunctional capabilities, humidity sensing tests were carried out. The results demonstrate that the sensor has a detection limit reaching the level of 0.12 ‰. These findings go beyond the scope of conventional interference optical coatings and highlight the potential applications of this technology in gas sensing and biosensing domains.
