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

TL;DR

This study investigates ultrafast photoinduced phase separation in Pr(0.6)Ca(0.4)MnO(3) thin films, revealing a transient ferromagnetic metallic phase forms within the insulating phase within ten picoseconds upon photoexcitation.

Contribution

It demonstrates the ultrafast formation of a transient ferromagnetic metallic phase in Pr(0.6)Ca(0.4)MnO(3) thin films using time-resolved Kerr effect measurements, highlighting phase dynamics on picosecond timescales.

Findings

Transient ferromagnetic metallic phase forms within 10 ps.

Photoinduced phase change is substrate-independent.

Magnetic field dependence differs between static and photoinduced states.

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.