Terahertz Fingerprint Detection with Ultrahigh Sensitivity Using 1D Photonic Crystal Cavity

A Terahertz (THz) fingerprint detection system using a 1D photonic crystal (PhC) cavity is designed for ultrahigh sensitivity. By leveraging cavity defect modes, this approach enhances light-matter interactions, enabling precise molecular fingerprint detection. The photonic band gap (PBG) confines electromagnetic waves at specific resonant frequencies, improving detection accuracy.CST simulations analyze the effects of mesh refinement and stack number on performance. Results show that finer mesh refinement enhances resonance accuracy, while increasing stacks improves wave confinement and detection sensitivity. However, excessive stacks raise computational complexity without significant gains. This study optimizes sensitivity while maintaining efficiency, making it highly suitable for applications in biomedical diagnostics, security screening, and material identification.