High-quality antiferromagnetic EuTiO3 epitaxial thin films on SrTiO3 prepared by pulsed laser deposition and postannealing

We report on epitaxial growth and magnetic properties of EuTiO3 thin films with a perovskite structure. Single crystalline EuTiO3 films with atomically flat surface are grown on (001) surface of SrTiO3 by pulsed laser deposition (PLD) and subsequent annealing in reducing atmosphere. The as-deposited films possess the crystal structure with an elongated c-axis and tend to stabilize ferromagnetically ordered Eu2+ spins at low temperatures. Postannealing at 1000 °C relaxes the out-of-plane lattice strain, and brings about a drastic change in magnetic structure; the annealed film becomes an antiferromagnet below Néel temperature of 5.1 K. The change in magnetic properties accompanied by the modification in lattice constant is discussed.