X-Ray Sources

X-Ray Sources

One of the main goals within the ELI scientific community is to produce ultra-short X-ray beamlines, both coherent and incoherent ones, to pave the way toward imaging nature with atomic resolution in space as well as time using devices that are suitable for university labs. Applications range from structure analysis in solid-state, atomic physics and molecular chemistry via imaging applications in medicine and the life sciences through to the discovery of the basic building blocks of life.

The X-ray laser-based sources developed at the ELI-Beamlines facility have the capability, unlike large-scale facilities such as third-generation synchrotrons or X-ray free-electron lasers (XFELs), to offer a much broader accessibility because only a few large-scale facilities exist throughout the world. In addition to reducing size and costs, these X-ray sources provide intrinsic synchronization between the optical driver laser and the X-ray pulses that are generated, as well as the full spectrum of different X-ray sources that each deliver specific properties.

Four paths have been developed within the ELI research area for transforming optical laser pulses into brilliant bursts of X-rays:

  • High-order harmonic generation 
  • Incoherent plasma X-ray sources
  • Betatron/Compton radiation
  • Laser-driven X-ray free-electron lasers.

For each of these research areas, dedicated beamlines will be built to provide a unique combination of X-ray sources to the user community. This is the mission of the Research Activity 2 (RA2). The RA2 application has a well-defined balance between fundamental science and applications in different fields of science and technology. Emphasis will be placed on providing an international user facility. Therefore, most of the areas have been conceived so that potential users from different fields will be attracted by the advanced laser parameters concerning pulse widths, repetition rates, broad wavelength ranges and intensities. Another important feature will be the combination of perfectly synchronized sources of short pulse coherent optical radiation, UV radiation, XUV radiation and X-ray radiation (coherent and incoherent). The available wavelength range of short pulses will be extended in the future to the gamma range well above 100 keV.

Laser Undulator X-Ray Source (LUX)

The Laser-driven Undulator X-ray source (LUX) is designed to provide users with few-nm, few-fs X-ray pulses combined with two auxiliary beams with pulse durations < 30 fs and < 7 fs at 10 Hz repetition rate. The main challenge in this research and development is the long-term stability of the X-ray pulses that are generated. The development of the LUX beam line is one of the steps toward stable laser-driven free-electron lasers.

High-order Harmonic Generation (HHG)

The mechanism of high-order harmonic generation in gas will be employed in a kHz beam line of ultra-short pulses of tunable coherent EUV–soft X-ray radiation that will be installed in the E1 hall of the ELI-Beamlines facility.

Plasma X-Ray Sources (PXS)

In a PXS source laser, pulses are focused on a renewing solid-density target and produce plasma. Hard x-rays are then emitted from the plasma. These contain both continuum radiation and x-ray lines, and have a duration of 100s femtoseconds.

Laser-driven Betatron and Compton Radiation

The source of Betatron X-rays are electrons that are trapped in the ion cavity. They are positioned in the wake of the laser pulse—which is propagating in a gas—and perform oscillations caused by electrostatic forces generated by charge separation. These oscillations generate broadband radiation in the X-ray spectral domain.

Compton scattering source operates by colliding a relativistic electron bunch with an intense laser pulse. This interaction leads emission of hard X-ray (from tens of keV up to MeV) due to a double Doppler upshift of incident photon energy by relativistic electrons.

Group leader:

Jaroslav Nejdl


Lukas Pribyl (LUX)

Michaela Kozlova (Betatron)

Dong-Du Mai (PXS)

Uddhab Chaulagain (Betatron)

Julien Gautier (HHG)

Spencer Jolly (LUX)

Vincent Leroux (LUX)

Byunghoon Kim (LUX)

Kim Ta Phuoc (Betatron)

Natalie Nowak (PXS)


Martin Albrecht

Karel Bohacek

Victoria Nefedova

Jan Vábek

Tomas Kerepecky 

Jakub Vančura

Ondřej Finke


Dariusz Kocoň (LUX)

Victor Martin (LUX)