Chinese Physics B

Rydberg-Atom-Based Terahertz Reflection System for Full-Field Imaging of Surface Characteristics

X J Li, Yu Wu, Bin Zhang, Qi-Rong Huang, Jun Wan, H. W. Zhao, Tao Li, Xin-Yu Yang, Lie Feng, Kai-Qing Zhang, Wei Huang, Hai-Xiao Deng

Published Jul 17, 2026• 0 citations

Publisher

Abstract

Abstract Rydberg-atom–based Terahertz (THz) reflection imaging provides ultra-high sensitivity and, in principle, the potential for MHz-level imaging speed, overcoming the limitations of THz transmission imaging for strongly absorbing samples. Here, we experimentally demonstrate a Rydberg-atom THz reflection imaging system, converting reflected THz fields into visible fluorescence using a cesium vapor cell along the 14 P 3/2 → 13 D 5/2 → 6 P 3/2 pathway, and sequentially imaging the fluorescence with a sCMOS camera. The system achieves clear reflection images with a minimum resolvable line-pair period of approximately 1.26 mm, and a minimum detectable power of 2.41 fW·s -1/2 per (6.5×6.5) μ m 2 pixel. Representative applications include reflection imaging of metallic samples, discrimination of Polar Liquids, and non-contact visualization of superficial human vasculature and finger motion. This system offers a promising route toward high-frame-rate, room-temperature, full-field THz imaging for both industrial and scientific applications.

DOI: 10.1088/1674-1056/ae8c1a

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