Figure 6
(Left) Two-color FEL pulses, and , tuned across the Ti M-resonance, impinge on a Ti grating with a temporal separation Δt. (Right) Diffraction patterns corresponding to single-color `pump' and `probe' pulses and to two-color `pump'–`probe' pulses (delayed by 500 fs) for different flux (F) regimes: low-F = 10–30 mJ cm−2, high-F = 2 J cm−2. |