Ultrafast structural phase transition driven by photoinduced melting of charge and orbital order.
نویسندگان
چکیده
We use femtosecond x-ray diffraction to probe directly the structural dynamics of a charge ordered and orbitally ordered thin film of La0.42Ca0.58MnO3 initiated by an ultrafast optical pulse. At low excitation fluences we observe the displacive excitation of a coherent optical A(g) 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.
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عنوان ژورنال:
- Physical review letters
دوره 103 15 شماره
صفحات -
تاریخ انتشار 2009