New lab for electron accelerator

The new laboratory will be an extension to the reactor building. There was a small gathering to celebrate the start of the construction last Monday 18 December 2017.

The new lab for materials research will be called APPEAL, which stands for Advanced Picosecond Pulsed Electron Accelerator Laboratory. The accelerator produces ultrashort flat fronts of electrons that hit targets at almost the speed of light.

“Studying the interaction of electrons with materials tells us about the material properties,” says Professor Laurens Siebbeles (Faculty of Applied Sciences). “It allows us to develop new materials for solar cells, LEDs, transistors or nano-electronics.”

The accelerator is not new and will be moved in from the Julianalaan. But because of the bunker’s 1.6 metre thick walls, and hence better protection from X-rays, the accelerator may finally be operated at full power. The pulse rate will be increased from 10 to 100 pulses per second, while the maximum energy will be amplified from 3 to 4.5 MeV.

Another enhancement is the terahertz detection about which Siebbeles comments: “We will soon be able to look deep inside the material and see exactly how the electrons move there, without having to touch the material itself.”

Technician Wybe Roodhuyzen, Professor Laurens Siebbeles and technician Martien Vermeulen at the building site. (Photo: Jos Wassink)

The laboratory, which will cost over 2 million euros to build, will be ready for research by mid-2018. The costs of the electron accelerator involve a similar amount and were covered by an NWO Vici grant that Siebbeles received in 2004 and several other grants he obtained after that.