Epitaxial Synthesis and Electronic Properties of Double-Perovskite Sr2TiRuO6 Films

We study the epitaxial structure and physical properties of B-site-ordered Sr 2 TiRuO 6 double-perovskite films by pulsed-laser deposition. The Ti/Ru order was evaluated (up to ${\sim}67$%) from intensity profiles of the out-of-plane reflections measured using a synchrotron-light source. The electronic states were investigated as a function of the Ti/Ru order. A systematic increase in resistivity with the Ti/Ru order was observed, which is associated with the localization behavior of Ru 4d electrons as verified by photoemission spectroscopy. These results suggest that the electronic properties of Sr 2 TiRuO 6 are strongly influenced by the 4d state connectivity between neighboring Ru atoms.