A team of researchers at the University of Ottawa developed a terahertz (THz) spectroscopy technique for recording movies in real time at 50,000 fps. High-speed video captures and slow-motion movies allow scientists to observe the mechanical dynamics of complex phenomena in detail. When the images in each frame are replaced by THz waves, the movies make it possible to monitor low-energy resonances and fast structural and chemical transitions in sample materials. As a result, the THz spectroscopy system, developed in collaboration with researchers from the Max Planck Institute for the Science of Light, could become a powerful tool for observing phenomena that are currently impossible to investigate because they are too fast, nonreproducible, or both. The system combines two spectroscopy techniques — chirped-pulse spectral encoding and a photonic time-stretch technique — with fast detection electronics. The first technique imprints the information carried by a THz pulse onto a chirped ...