Polarization-insensitive terahertz antibiotic sensor based on a compact structure

Efficient antibiotic detection in biological and environmental samples is crucial for public health and safety, but traditional methods face limitations in sensitivity and stability, making the development of robust, polarization-insensitive terahertz (THz) sensors a vital challenge. A polarization-insensitive terahertz (THz) antibiotic sensor is proposed by employing a graphene-based metamaterial structure, offering significant enhancements in sensitivity and operational stability. The sensor design features graphene resonators integrated with a quartz substrate, utilizing its low-loss properties and dynamic tunability. The design is optimized for maximum electromagnetically induced transparency (EIT) effect in the THz range, ensuring consistent performance under varying electromagnetic conditions. The sensor achieves over 500 GHz/refractive index unit (RIU) sensitivity under both x and y polarization states. Graphene's tunability allows for effective response adjustment across a broad frequency bandwidth, essential for diverse antibiotic detection. This graphene-enhanced sensor marks a significant advance in the THz sensing, offering high sensitivity, extensive tunability, and polarization insensitivity, making it suitable for complex biomolecular detection in medical diagnostics and environmental monitoring.