Ferromagnetism stabilization of ultrathin SrRuO3 films:: Thickness-dependent physical properties

Ultrathin films of SrRuO(3) (SRO) have been grown on SrTiO(3) (001) substrates to study thickness-dependent physical properties. We have revealed the existence of two critical film thicknesses where a metal-insulator transition occurs at a film thickness of 4-6 ML (monolayer) and the value of Curie temperature saturates at about 15 ML. The electrical and magnetic properties are well correlated with the thickness-dependent evolution of surface morphology of the ultrathin SRO films. These experimental results suggest the importance of the disorder associated with the unique growth mode transition in SRO films. (C) 2006 American Institute of Physics.