Ultrasensitive Terahertz Detection via Different Novel Metasurfaces

In recent decades, Terahertz (THz) bioanalytical sensors are considered as an excellent sensing platform due to the advantages such as label-free, accurate, nonionizing, high signal to noise ratio, and non-damaging [1–10]. It is able to distinguish biological sample features including structure, composition, molecular rotation modes and vibration modes rapidly. However, the lack of powerful radiation sources hinders the use of them. Also, weak light-matter interactions due to the mismatch between THz wavelengths and the absorption of bio-molecules has become the main disadvantages, restricting the sensitivity of THz-based biosensors [11–13]. To optimize the performance of THz biosensors, we proposed various advanced methods such as giant near-field enhancement around the metasurface-analytes boundary via quasi-BICs [14], shifting Lorentz-lattice coupled-resonance to electromagnetism-induced transparency (EIT) by photoexcitation of the silicon bridge [15], and widening spectral range via synchronous regulating graphene and C-shape rings [16]. Our results show that these THz metasurfaces bring light into next generation of trace biological substances sensing system.