Metal‐Hybrid Optical Tamm Cavity THz Detector With High Quality Factor

Abstract

Terahertz (THz) optical cavities are essential for enhancing light–matter interactions, yet achieving high‐quality‐factor resonators with practical fabrication and direct device integration remains challenging. Here, we demonstrate a Nb 5 N 6 microbolometer embedded in a hybrid metal–optical Tamm cavity (MOTC), experimentally achieving a Q factor of 1088 at approximately 0.625 THz. The MOTC combines the advantages of Tamm and optical Tamm configurations: an additional distributed Bragg reflector (DBR) suppresses metal‐induced loss, while the bottom Au mirror eliminates transmission leakage. The detector and DBRs are fabricated separately and subsequently assembled, avoiding complex monolithic integration and providing a modular architecture potentially compatible with large‐area detector arrays. Although the highest voltage responsivity occurs at a lower Q configuration, the detector response is jointly determined by local‐field enhancement and detector–cavity impedance matching. A reduced‐order equivalent coupling model is developed to capture the combined effects of local‐field enhancement and detector–cavity impedance matching, providing guidance for balancing cavity enhancement and detector responsivity. The high Q factor provides extended photon lifetimes and enhanced cavity fields, making the MOTC a promising platform for cavity‐enhanced THz detection and light–matter interactions.