Temperature-dependent X-ray absorption near edge spectroscopy of doped LaMnO3: Ion-size and the Jahn–Teller distortion effects

The temperature-dependent X-ray absorption near-edge spectroscopy (XANES) of LaMnO3 thin films doped with various divalent ions was systematically carried out to investigate the effects of the ion size and associated Jahn–Teller distortions (JTDs) on the electronic structure modifications. Doped LaMnO3 thin films were grown on (1 0 0) SrTiO3 and (1 1 0) NdGaO3 substrates by pulsed-laser deposition with typical thickness of 250–300 nm. Temperature-dependent resistivity ρ(T) and magnetization M(T) were measured. The results indicate that the drastic changes in magneto-transport properties induced by the substitution of A-site ion and the splitting of the O K-edge pre-edge peak associated with the eg(↑) and t2g(↓) energy levels at low temperatures in La1−xCaxMnO3 and La1−xSrxMnO3 (x=0.3, 0.375) may both relate to the lattice disorder and the associated JTD effects on modifying the electronic structure of doped-LaMnO3.