Effect of Co doping on the magnetotransport properties of La0.45Sr0.55MnO3 perovskite

Y. Ying, N. V. Dai, T. W. Eom, Y. P. Lee

doi:10.1063/1.3117186

Effect of Co doping on the magnetotransport properties of La0.45Sr0.55MnO3 perovskite

Y. Ying

Hanyang University Department of Physics and q-Psi, , Seoul 133-791, Republic of Korea
N. V. Dai

Hanyang University Department of Physics and q-Psi, , Seoul 133-791, Republic of Korea
T. W. Eom

Hanyang University Department of Physics and q-Psi, , Seoul 133-791, Republic of Korea
Y. P. Lee

Hanyang University Department of Physics and q-Psi, , Seoul 133-791, Republic of Korea

説明

<jats:p>We investigated the magnetotransport properties of polycrystalline La0.45Sr0.55Mn1−xCoxO3 (0≤x≤0.15). Ferromagnetism is enhanced with the doping of Co ions in La0.45Sr0.55MnO3, but the antiferromagnetism is nearly destroyed in the low-temperature region. The Mn3+–Mn4+ double-exchange (DE) and Co2+–Mn4+ ferromagnetic (FM) superexchange interactions are mainly responsible for the magnetic properties of the doped system. With increased Co doping, the insulating properties and the magnetoresistance (MR) effect are simultaneously enhanced. This indicates that the Co doping strengthens both the Mn3+–Mn4+ DE and Co2+–Mn4+ FM superexchange interactions. The Co doping increases the disorder in the system, causing the MR effect to increase with decreasing temperature.</jats:p>