Enhanced trace-amount terahertz vibrational absorption spectroscopy using surface spoof polarization in metasurface structures

Autor: Xiang-Jun Li, Chan Ma, De-Xian Yan, Shi-Hui Guo, Le Zhang, Ji Yang, Yang Zhao, Wei-Dong Zhou
Rok vydání: 2022
Předmět:
Zdroj: Optics letters. 47(10)
ISSN: 1539-4794
Popis: Terahertz (THz) absorption spectroscopy is a powerful tool for molecular label-free fingerprinting, but it faces a formidable hurdle in enhancing the broadband spectral signals in trace-amount analysis. In this paper, we propose a sensing method based on the geometry scanning of metal metasurfaces with spoof surface polarization sharp resonances by numerical simulation. This scheme shows a significant absorption enhancement factor of about 200 times in an ultra-wide terahertz band to enable the explicit identification of various analytes, such as a trace-amount thin lactose film samples. The proposed method provides a new, to the best of our knowledge, choice for the enhancement of wide terahertz absorption spectra, and paves the way for the detection of trace-amount chemical, organic, or biomedical materials in the terahertz regime.
Databáze: OpenAIRE