Probing strain propagation in nanostructured perovskites by ultrafast x-ray diffraction

Propagating strain waves in SrTiO
3
with amplitudes of Δa(t)/a
0
≈ 10
⁻⁴
launched from a PbZr
0.2
Ti
0.8
O
3
film are measured by x-ray diffraction. The shape of the picosecond transients depends nonlinearly on the strain amplitude due to x-ray interference.