Laser-Induced Transient Structural Changes in Ag(111) Studied by Time Resolved X-ray Diffraction

The transient lattice changes on the Ag(111) crystal due to acoustic wave propagation after excitation with femtosecond pulses was studied by means of time resolved X-ray diffraction. The lattice disorder after UV irradiation is detected by changes of the XRD rocking curve shift, broadening, and total diffraction intensity as a function of time. We have observed a blast force formed within two picoseconds after fs UV irradiation. Experimental results show an initial lattice contraction followed by lattice expansion that propagates with sound velocity.