Electronic and magnetic structure of (Ca,Sr)RuO3 thin films

The 4d transition metal oxide (Ca,Sr)RuO3 exhibits ferromagnetic order in the doping range 0.4 ≤ x ≤1 while it is a paramagnetic metal for x < 0.4. Since (Ca,Sr)RuO3 remains essentially isostructural and has a similar electronic configuration throughout the doping series, the differences in the magnetic properties might be attributed to chemical pressure effects. To verify a possible dependence of direction and/or magnitude of the magnetic moments on pressure, (Ca,Sr)RuO3 films were deposited on different substrates (LSAT, STO, DyScO3=DSO). The magnetic and electronic structure of the samples was studied by soft x-ray absorption and magnetic circular dichroism at the Ru M2,3 and O K edges. In addition, depth-dependent information on element-specific core levels was obtained by varying the photon energy in soft x-ray photoemission spectroscopy. Various implications will be discussed.