Figure 4. Imprints created by hard XFEL pulses focused with an Ir-filled diamond FZP.

The Au-coated glass substrates are viewed under an angle of 45°. (a) An unattenuated pulse (∼5×10⁻⁵ J) causes a crater with an inner diameter of 3.5 µm. (b, c) Imprints at ∼5×10⁻⁷ J and 1×10⁻⁷ J result in diameters of 1.1 µm and 690 nm, respectively. (d–f) pulses at ∼2×10⁻⁸ J result in peak fluences close to the ablation threshold of the Au coating. The imprint diameters are 325, 240, and 190 nm. A fountain of molten glass ejected from the substrate and solidified in the center of imprints c–f.