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arXiv · 0905.4016

Ultrafast photoinduced phase separation dynamics in Pr(0.6)Ca(0.4)MnO(3) thin films

T. Mertelj·R. Yusupov·A. Gradisek·M. Filippi·W. Prellier·D. Mihailovic
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Abstract

The time resolved Magnetooptical Kerr effect in the substrate-strain-induced insulating ferromagnetic phase in (Pr$_{0.6}$Ca$_{0.4}$)MnO$_3$ thin films on two different substrates was measured in a magnetic field up to 1.1T. The photoinduced Kerr rotation and ellipticity show remarkably different magnetic-field dependence. From the comparison of the magnetic field dependencies of the photoinduced and static Kerr rotation and ellipticity we conclude that a transient ferromagnetic metallic phase, embedded within the insulating ferromagnetic phase, is created upon the photoexcitation at low temperatures. A comparison of temporal dependence of the photoinduced Kerr signals with the photoinduced reflectivity indicates the change of the fractions of the phases takes place on a timescale of ten picoseconds independent of the substrate.

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T. Mertelj, R. Yusupov, A. Gradisek, M. Filippi, W. Prellier, D. Mihailovic. 2009-05-25. Ultrafast photoinduced phase separation dynamics in Pr(0.6)Ca(0.4)MnO(3) thin films. https://doi.org/10.1209/0295-5075/86/57003

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