Full-Field Terahertz Imaging at Kilohertz Frame Rates Using Atomic Vapor

There is much interest in employing terahertz (THz) radiation across a range of imaging applications, but so far, technologies have struggled to achieve the necessary frame rates. Here, we demonstrate a THz imaging system based upon efficient THz-to-optical conversion in atomic vapor, where full-field images can he collected at ultrahigh speeds using conventional optical camera technology. For a 0.55-THz field, we show an effective 1-cm(2) sensor with near diffraction-limited spatial resolution and a minimum detectable power of (190 +/- 30) fW s(-1/2) per (40 x 40) mu m(2) pixel capable of video capture at 3000 frames per second. This combination of speed and sensitivity represents a step change in the state of the art of THz imaging and will likely lead to its uptake in wider industrial settings.