The external antenna on the detector captures long-wave infrared and terahertz radiation and funnels it to a graphene flake which is located in the center of the structure. Credit: M. Mittendorff
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), working with colleagues from the US and Germany, have developed a new optical detector from graphene which reacts very rapidly to incident light of all different wavelengths and even works at room temperature. It is the first time that a single detector has been able to monitor the spectral range from visible light to infrared radiation and right through to terahertz radiation. The HZDR scientists are already using the new graphene detector for the exact synchronization of laser systems.
A tiny flake of graphene on silicon carbide and a futuristic-looking antenna, and there it is - the new graphene detector. Like no other single detector system which has gone before, this comparatively simple and inexpensive construct can cover the enormous spectral range from visible light all the way to terahertz radiation. "In contrast to other semiconductors like silicon or gallium arsenide, graphene can pick up light with a very large range of photon energies and convert it into electric signals. We only needed a broadband antenna and the right substrate to create the ideal conditions," explained Dr. Stephan Winnerl, physicist at the Institute of Ion Beam Physics and Materials Research at the HZDR.