We have designed and constructed a unique series of gyrotrons. These are electron tubes that generate millimetre-submillimetre wavelength electromagnetic radiation. We have used them to study plasmas and solid materials at these wavelengths. Current work aims to generate the short submillimetre wavelengths more efficiently.

Other millimetre-wave work includes the design of specially configured blazed gratings to produce beams of radiation with phase singularities, demonstrations of geometric phase, and the Bragg reflection of surface electromagnetic waves by a photo-induced grating produced by shining a pattern of light on a semiconductor wafer.

For further information see http://www.physics.usyd.edu.au/plasma/gyro.html.