The FELIX group has constructed 2 free electron lasers (FEL) using undulators supplied by Daresbury Laboratory. Secondary emission electron spectrometers were supplied by Dundee Institute of Technology and fast infrared detectors by Heriot-Watt University. Studies on quantum structures have been carried out, and on photoablation of eye tissue.
The CLIO FEL has been developed to a stage where it operates in the range 1.8 to 17.5 microns with peak power of several MW in 0.5 to 10 ps pulses. The average power is adjustable up to a few watts. Studies which have been carried out include nonlinear absorption in semiconductors and short pulse effects in the FEL itself.
FELs have been developed at ENEA to operate in the far infrared and submillimetre regions. A Cherenkov FEL produces up to 50 W in the range 800 to 1600 microns. A compact FEL employing a short period undulator has also been built, and now delivers about 10 kW in 60 ps pulses at 3 GHz in the range 2 to 3 mm.
The Darmstadt FEL group has constructed an infrared laser which makes use of the 35 to 50 MeV electron beam delivered by the superconducting electron accelerator S-DALINAC. Lasing is expected in the region 2.5 to 7.0 microns.
Groups from the Universities of Twente and Eindhoven have investigated the fabrication of caesium potassium antimonide and have achieved a maximum efficiency of 7% for a lifetime of several days. A hybrid undulator has been constructed and beam characterization is in progress. Beam currents up to 300 A at 6 MeV have been obtained, and will be used as the injector to a 25 MeV racetrack microtron.
Work has been carried out in Lille on the analysis of stability and instability conditions in the long pulse regime in an electrostatic FEL. The exploitation of far infrared FELs as pollution detectors has been examined.
Funds are requested to set up a European network for scientific exchange involving seven (Far)-Infared Free Electron Laser projects. The proposal describes plans for frequent interaction between researchers, for the development of some hardware specific to (F)IR-FEL operation, and for the establishment of a European FEL users community.
Funding SchemeCSC - Cost-sharing contracts
00060 Santa Maria Di Galeria Roma
EH14 4AS Edinburgh
OX1 3RH Oxford
DD1 1HG Dundee