Second-order autocorrelation of XUV FEL pulses via time resolved two-photon single ionization of He

作者：Moshammer R^*; Pfeifer Th; Rudenko A; Jiang Y H; Foucar L; Kurka M; Kuehnel K U; Schroeter C D; Ullrich J; Herrwerth O; Kling M F; Liu X J; Motomura K; Fukuzawa H; Yamada A; Ueda K; Ishikawa K L; Nagaya K; Iwayama H; Sugishima A; Mizoguchi Y; Yase S; Yao M; Saito N; Belkacem A; Nagasono M; Higashiya A; Yabashi M; Ishikawa T; Ohashi H; Kimura H; Togashi T

来源：Optics Express, 2011, 19(22): 21698-21706.

Second-order autocorrelation spectra of XUV free-electron laser pulses from the Spring-8 Compact SASE Source (SCSS) have been recorded by time and momentum resolved detection of two-photon single ionization of He at 20.45 eV using a split-mirror delay-stage in combination with high-resolution recoil-ion momentum spectroscopy (COLTRIMS). From the autocorrelation trace we extract a coherence time of 8 +/- 2 fs and a mean pulse duration of 28 +/- 5 fs, much shorter than estimations based on electron bunch-length measurements. Simulations within the partial coherence model [Opt. Lett. 35, 3441 (2010)] are in agreement with experiment if a pulse-front tilt across the FEL beam diameter is taken into account that leads to a temporal shift of about 6 fs between both pulse replicas.

• 出版日期2011-10-24
• 单位RIKEN