Abstract
We use femtosecond x-ray diffraction to probe directly the structural dynamics of a charge ordered and orbitally ordered thin film of initiated by an ultrafast optical pulse. At low excitation fluences we observe the displacive excitation of a coherent optical phonon. Under high excitation conditions we observe a complete phase transition within 1 ps via the disappearance of a superlattice reflection. The initial step of the phase transition occurs on a time scale significantly faster than the 200 fs time resolution of our experiment.
- Received 7 July 2009
DOI:https://doi.org/10.1103/PhysRevLett.103.155702
©2009 American Physical Society