Carbon nanotubes + highly sensitive photoacoustic sensing = THz power detector:
Sucheta Sharma, Mohsen Ahmadi, Jussi Rossi, Markku Vainio, Zhipei Sun, Andreas Steiger, and Erkki Ikonen, "Terahertz radiation detection with a cantilever-based photoacoustic sensor," Opt. Express 30, 43417-43425 (2022)