Identification of octahedral configuration in strained SrRuO3 thin films

The compressively strained (2 2 0)-oriented SrRuO 3 epitaxial thin films were grown on c -plane SrTiO 3 substrates using pulsed laser deposition. Temperature-dependent lattice changes associated with structural phase transition were investigated through in-situ X-ray diffractions with varying temperature ranges from 25 to 650 °C under atmospheric conditions. Strong modulation of the in-plane lattices between the strained SrRuO 3 thin film and SrTiO 3 substrate was observed. The structural phase transition from pseudo-orthorhombic to the tetragonal structure was determined at around 285 °C and epitaxial strain was persistent during the structural phase transition in the fully strained SrRuO 3 /SrTiO 3 heterostructured thin film. Crystal symmetry and the corresponding RuO 6 octahedral configurations were verified that the compressively strained SrRuO 3 thin film has pseudo-orthorhombic (monoclinic, P2 1 / m , #11) structure with the B O 6 configuration of a + a – c – at 25 °C and tetragonal ( I 4/ mcm , #140) with the octahedral tilt of a 0 a 0 c – above 285 °C through structural model calculations based on the diffraction data of 20 individual half-order peaks.