Research team paves the way for compact, inexpensive free-electron lasers

Extremely short and intensive light flashes are in great demand to investigate atoms, molecules and new materials. free-electron lasers (FELs) produce these flashes. But around the world, the beam time available at large- scale user facilities is in short supply and waiting times are long. Researchers at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and the Synchrotron SOLEIL near Paris have taken a crucial step along this path: for the first time, they managed to operate a laser-plasma FEL in a stable and reproducible manner in the so-called high-gain regime – an operating state with particularly high amplification of the radiation generated.

In the undulator, the electron beam from a compact laser-plasma accelerator interacts with a laser pulse. This interaction enhances the generated FEL radiation and enables higher pulse energies.