A new solid-state source of submillimetre-wave radiation has been created at the University of Leeds in the UK. By extracting the third-harmonic from an InP Gunn device, Dr Heribert Eisele at the Institute of Microwaves and Photonics is the first to demonstrate that a single room-temperature semiconductor device, which can simply be connected to a power supply such as a battery, can generate significant power at 480 GHz. This result could lead to inexpensive, reliable and compact oscillators which would greatly benefit a range of applications, including wireless networks with greatly increased bandwidth.