Epitaxial thin films of strontium iridate (110)SrIrO3 were obtained by radio-frequency magnetron sputtering on single-crystal substrates of (110)LaAlO3 and (110)Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT). The structural features, surface morphology, electronic structure, and electrical transport properties are studied. X-ray diffraction analysis revealed different epitaxial mismatches: m = 4.49% for SrIrO3/LaAlO3 and –1.49% for SrIrO3/PMN–PT, which leads to a change in the pseudocubic cell volume to 56.9 10−3 nm3 and 63.4 × 10−3 nm3, respectively. Atomic force microscopy revealed a granular morphology of the SrIrO3 films with a root-mean-square roughness RMS ~ 6 nm, indicating three-dimensional growth. An analysis of the temperature dependences of electrical resistance R(T) revealed different effects of the mechanism of electron scattering on localized magnetic moments on the electrical resistance of SrIrO3/LaAlO3 and SrIrO3/PMN-PT (RKondo coefficients = 169 and 17 Ω, respectively). Using X-ray photoelectron spectroscopy, the spin–orbit splitting of Ir 4f was determined for SrIrO3 films grown on (110)LaAlO3 and PMN–PT substrates; it was 2.91 and 3.10 eV, respectively. The results demonstrate the influence of the degree of epitaxial mismatch on the structure, transport, and local electronic structure of SrIrO3.
Baydikova et al. (Mon,) studied this question.