Ali Wajid, Liu Weitao, Liu Ye, Li Ziwei
Hunan Institute of Optoelectronic Integration, College of Materials Science and Engineering, Hunan University, Changsha 410082, China.
Department of Civil, Environmental & Geomatic Engineering, University College London, London WC1E 6BT, UK.
Nanomaterials (Basel). 2023 Sep 28;13(19):2668. doi: 10.3390/nano13192668.
Plasmonic nanostructures as narrowband perfect absorbers have garnered significant attention due to their potential applications in biosensing and environment detection. This study emphasizes the investigation of arrayed split ring nanostructures within the configuration of metal-insulator-metal (MIM) multilayers, resulting in a maximum light absorption of 99.94% in the near-infrared (NIR) spectral range. The exceptional absorption efficiency of the device is attributed to the strong resonance of electric and magnetic fields arising from the Fabry-Pérot cavity resonance. The resonant peak can be flexibly tuned by engineering the dielectric layer thickness, the period, and the geometric parameter of split rings. Remarkably, the device exhibits promising capabilities in sensing, demonstrating a sensitivity of 326 nm/RIU in visible wavelengths and 504 nm/RIU in NIR wavelengths when exposed to bio-analytes with varying refractive indices. This designed nanostructure can serve as a promising candidate for biosensors or environmental detection.
等离子体纳米结构作为窄带完美吸收体，因其在生物传感和环境检测中的潜在应用而备受关注。本研究着重对金属-绝缘体-金属（MIM）多层结构中的阵列式裂环纳米结构进行研究，结果表明在近红外（NIR）光谱范围内最大光吸收率可达99.94%。该器件卓越的吸收效率归因于法布里-珀罗腔共振产生的强电场和磁场共振。通过设计介电层厚度、周期和裂环的几何参数，可以灵活调节共振峰。值得注意的是，该器件在传感方面展现出良好的性能，当暴露于具有不同折射率的生物分析物时，在可见光波长下灵敏度为326 nm/RIU，在近红外波长下灵敏度为504 nm/RIU。这种设计的纳米结构有望成为生物传感器或环境检测的候选材料。
