A photograph of the custom-built laser chamber, which receives simultaneously a pulse of helium gas and a pulse from RIKEN’s free-electron laser, which is known as the SPring-8 Compact SASE Source (SCSS). The resulting blue-green superfluorescence is visible.
A variety of imaging technologies rely on light with short wavelengths because it allows very small structures to be resolved. However, light sources which produce short, extreme ultraviolet or x-ray wavelengths often have unstable emission wavelength and timing. Now, by illuminating a gas with a powerful laser, a research team in Japan has demonstrated a light source that may solve many of these problems. The research was published by Mitsuru Nagasono, from the RIKEN SPring-8 Center in Harima, and his colleagues from RIKEN and three other institutes.
More information: Nagasono, M., et al. Observation of free-electron-laser-induced collective spontaneous emission (superfluorescence). Physical Review Letters 107, 193603 (2011).