Strain-stabilized charge ordering and magnetorelaxor behaviors in Cr-dopedPr0.5Ca0.5MnO3 epitaxial thin films

Thin films of a magnetorelaxor compound, Pr0.5Ca0.5Mn1-yCryO3 were grown on various substrates. Strain-free and polycrystalline thin films on MgO subs trates well reproduce the properties reported for the bulk samples. Pseudom orphically strained and atomically smooth epitaxial thin films grown on per ovskite substrates show strain-driven modification of the properties. Being consistent with the orbital ordering accompanied with charge ordering, ten sile strain anomalously stabilizes the charge-ordered (CO) state. Compressi ve strain also suppresses ferromagnetism but high-Cr doping (y=0.10) induce s magnetorelaxor behaviors, where the volume ratio of coexisting CO and fer romagnetic phases can be tuned and memorized by the history of the magnetic -field application. (C) 2001 American Institute of Physics.