Science@FELS

Session

Science Specific FEL Operation

24 Sept 2026, 08:30

Auditorium (WHGA/001) (Paul Scherrer Institut)

98. Spectator-nuclei reveal nonlinear light-matter interaction driven by an X-ray free-electron laser (Tutorial)

Ralf Röhlsberger (Helmholtz Institut Jena)

24/09/2026, 08:30

Invited

the abstract, based on the word template given on this website, is provided in the attachment section of this page.

69. New opportunities at XFELs for Mössbauer science

Dr Miriam Gerharz (Max-Planck-Institut für Kernphysik)

24/09/2026, 09:10

Invited

Mössbauer spectroscopy is well established across the natural sciences. The exceptionally narrow linewidths of Mössbauer nuclei (e.g. 4.7 neV for Fe57) also make them a promising platform for x-ray quantum optics. These narrow transitions feature long lifetimes, but on the other hand also allowed to only study single excitations for decades. This limitation changed with the advent of X-ray...

95. Wave-packet manipulation via phase-locked schemes at a seeded free-electron laser

Carlo Callegari (Elettra - Sincrotrone Trieste S.C.p.A.)

24/09/2026, 09:35

Science with specific FEL operation

Invited

FERMI is the seeded free electron laser (FEL) facility in operation for international users within the Elettra – Sincrotrone Trieste research center. The adoption of a seeded design provides FERMI with the desirable qualities one expects from a laser: reproducibility, stability, spectral purity, synchronization, spatial and temporal coherence [1]. The latter implies that the electric field of...

34. X-ray chronoscopy in an optical pump – X-ray probe study

Dr Wojciech Błachucki (Institute of Nuclear Physics, Polish Academy of Sciences, Kraków, Poland)

24/09/2026, 10:00

Science with specific FEL operation

Oral

X-ray free electron lasers (XFELs) have revolutionized the study of matter, yet traditional optical pump - X-ray probe spectroscopy remains limited by arrival time jitter and probe pulse duration, often restricting temporal resolution to tens of femtoseconds. While current methods rely mainly on spectral changes and momentum transfer the ongoing development of time tools, for instance THz...

61. Attosecond metrology at XFELs

Dr Daniel Charles Haynes (PSI - Paul Scherrer Institut)

24/09/2026, 10:15

AMO Physics

Oral

Attosecond pulse modes at XFELs, such as those employing slotted-spoiler devices, low bunch charge, or photocathode shaping, are increasingly available at facilities around the world [1-3]. The intensity and photon energy of attosecond XFEL pulses greatly exceed those of conventional attosecond HHG pulses, granting the potential to study a much wider range of systems and processes than have...

96. Lasing of a Cavity-Based X-ray source

Harald Sinn (EuXFEL), Patrick Rauer (Deutsches Elektronen-Synchrotron DESY)

24/09/2026, 11:00

Invited

Cavity-based X-ray Free Electron Lasers (CBXFELs) promise to transform the field of hard X-ray science by delivering radiation with exceptional brilliance, stability,and full three-dimensional coherence. At the European XFEL, we have recently achieved lasing with multi-pass gain in a proof-of-concept CBXFEL featuring a 132.8m round-trip hard X-ray cavity using diamond crystals in Bragg...

8. Experimental Demonstration of Attosecond Soft and Hard X-ray Pulse Generation with Photocathode Shaping at SwissFEL

Dr Zhaoheng Guo (École Polytechnique Fédérale de Lausanne (EPFL), PSI - Paul Scherrer Institute)

24/09/2026, 11:25

Oral

We demonstrate the generation of both soft and hard X-ray attosecond pulses at SwissFEL, based on the temporal shaping of the photocathode laser pulses [1]. Through flexible bunch compression schemes, the electron beam current profile evolves from a double-Gaussian shape with 10 ps duration into a femtosecond-scale isolated high-current spike in the core of a tens-of-femtosecond-long electron...

11. Cross-correlation measurements of the Two-Color Dual Oscillator IR FEL at FHI Berlin

Akash Chandra Behera (Fritz Haber Institute of the Max Planck Society)

24/09/2026, 11:40

Solid State Physics

Oral

The infrared free-electron laser (IR-FEL) at the Fritz Haber Institute recently commissioned a two-color upgrade, enabling simultaneous lasing with two IR FEL oscillators with independently tunable wavelength. This is realized by employing a high-frequency (500 MHz) kicker cavity to feeding alternating electron bunches from within the 1 GHz bunch train into the two separate IR FEL oscillators....

117. Special operation modes from Instrument side (HXRSS / Attoseconds / Twin Pulses)

Joerg Hallmann (European XFEL)

24/09/2026, 11:55

22. Free electron lasers: a versatile tool to investigate metasurfaces

Amirmostafa Amirjani (Quantum Solid-State Physics, Department of Physics and Astronomy, KU Leuven, Belgium)

24/09/2026, 12:15

Solid State Physics

Oral

Metasurfaces, planar arrays of engineered subwavelength structures, enable unprecedented control over light’s amplitude, phase, and polarization, driving innovations in imaging, sensing, and active nanophotonics. For the optical characterization of these structures, tabletop optical parametric oscillators (OPOs) and amplifiers (OPAs) are widely used, as they provide rich information on linear...

102. X-ray FEL Science towards fusion (Tutorial part1)

Thomas Cowan (HZDR)

24/09/2026, 12:30

Tutorial

109. X-ray FEL Science towards fusion (Tutorial part2)

Harald Sinn (EuXFEL)

24/09/2026, 12:50

107. XFELO

Patrick Rauer (Deutsches Elektronen-Synchrotron DESY)

Invited