TY - JOUR AU - S Madhukar AU - S Aggarwal AU - A.M Dhote AU - Ramamoorthy Ramesh AU - A Krishnan AU - D Keeble AU - E Poindexter AB - We report on the metal-insulator transition of La0.5Sr0.5CoO3 thin films deposited by pulsed laser ablation on LaAlO3, substrates. The films were cooled in oxygen partial pressures between 760 and 10-5 Torr and electrical resistivity of the films was measured as a function of cooling oxygen pressure. La0.5Sr0.5CoO3 films changed from metallic to insulating behavior depending on their oxygen content. A defect model has been proposed to explain this transition and the change in conductivity is related to the change in the oxidation state of the cobalt ions. The model explains the relationship between oxygen partial pressure and electrical conductivity in La0.5Sr0.5CoO3, which describes the experimental dependence reasonably well. Positron annihilation studies were also done on the same set of samples and the S parameter was seen to increase by 8% from a fully oxygenated sample to a sample cooled in 10-5 Torr. © 1997 American Institute of Physics. BT - Journal of Applied Physics DO - 10.1063/1.364991 LA - eng M1 - 8 N1 - cited By 102 N2 - We report on the metal-insulator transition of La0.5Sr0.5CoO3 thin films deposited by pulsed laser ablation on LaAlO3, substrates. The films were cooled in oxygen partial pressures between 760 and 10-5 Torr and electrical resistivity of the films was measured as a function of cooling oxygen pressure. La0.5Sr0.5CoO3 films changed from metallic to insulating behavior depending on their oxygen content. A defect model has been proposed to explain this transition and the change in conductivity is related to the change in the oxidation state of the cobalt ions. The model explains the relationship between oxygen partial pressure and electrical conductivity in La0.5Sr0.5CoO3, which describes the experimental dependence reasonably well. Positron annihilation studies were also done on the same set of samples and the S parameter was seen to increase by 8% from a fully oxygenated sample to a sample cooled in 10-5 Torr. © 1997 American Institute of Physics. PB - American Institute of Physics Inc. PY - 1997 SP - 3543 EP - 3547 T2 - Journal of Applied Physics TI - Effect of oxygen stoichiometry on the electrical properties of La0.5Sr0.5CoO3 electrodes VL - 81 SN - 00218979 ER -