Author: Nold, J.
Paper Title Page
MOPB16 New Tunable DUV Light Source for Seeding Free-electron Lasers 38
 
  • N.Y. Joly, W. Chang, P. Hölzer, J. Nold, P.St.J. Russell, J.C. Travers
    Max Planck Institute for the Science of Light, Erlangen, Germany
  • M.-E. Couprie, M. Labat
    SOLEIL, Gif-sur-Yvette, France
 
  Seeding of single-pass free-electron lasers is a promising approach for improving the temporal coherence compared to self-amplified spontaneous emission [1], at the same time reducing the saturation length and reinforcing the harmonic level. Convention lasers or harmonics generated in gas are usually used as coherent seeds [1]. However such sources require complicated set-up and have limited tuneability. Here, we suggest the use of a newly discovered and efficient source of UV light, continuously tunable from 120 nm to 320 nm. The extremely compact and simple set-up consists of 20 cm of hollow-core photonic crystal fibre filled with a noble gas at variable pressure up to a few tens of bar and pumped by ~1 μJ 30 fs pulses at 800 nm [2]. The process relies on a favourable sequence of linear and nonlinear effects: low pressure-tunable dispersion, pulse compression due to a combination of self-phase-modulation and anomalous dispersion, self-steepening and dispersive wave generation. Tunable diffraction-limited DUV pulses of ~50 nJ and fs duration are generated. Seeding of FEL is discussed.
[1] G. Lambert et al., Nature Physics 4, 296-300 (2008)
[2] N. Joly et al., accepted in PRL