Dual-cameras terahertz imaging with multi-kilohertz frame rates and high sensitivity via Rydberg-atom vapor

Abstract Terahertz (THz) imaging holds increasing importance across various scientific fields and practical applications due to its unique characteristics. However, achieving high sensitivity and high frame rates simultaneously remains a major challenge for most current THz imaging techniques. In this paper, we demonstrate an improved THz imaging system based on Rydberg-atom vapor, which converts THz waves into visible fluorescence. A high-sensitivity camera and a high-speed camera are used simultaneously to capture the visible fluorescence. Specifically, for a 0.55 THz source, a sensor with a minimum detectable power of 41.7 aW/μm² at 100 fps and 43 fW/μm² at 6000 fps has been achieved simultaneously, with an effective imaging area larger than 100 mm². To demonstrate the spectral properties, the measured spectrum of the emitted fluorescence is presented with a high resolution of 0.1 nm. The demonstrated system can promote the development of the Rydberg-atom vapor based THz imaging technique to practical THz imaging frontier applications.