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Magnetic and Electric properties of La_{1-delta}MnO_{3}

S. de Brion·F. Ciorcas·G. Chouteau·P. Lejay·P. Radaelli·C. Chaillout
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Abstract

The magnetic phase diagram of $La_{1-δ}MnO_{3}$ powdered samples have been studied as a function of $δ$ in the low doping range. $La_{0.97}MnO_{3}$ has a canted magnetic structure at low temperature $(θ\simeq 130\QTR{group}{{}^{\circ}})$. Above $T_{C}=118K$, it becomes a paramagnet with a huge effective magnetic moment, $μ_{eff}=6.0μ_{B}$, reflecting the presence of magnetoelastic polarons which are not affected by the magnetic field (up to 20T) nor the temperature $(1.2T_{C}<T<2.5T_{C})$. When $δ$ is increased to $δ=0.07$, polarons are still presen at high temperature, with a smaller size: $μ_{eff}=5.8μ_{B}$. The system becomes fully ferromagnetic below 170K but remains insulating down to the lowest temperature.

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S. de Brion, F. Ciorcas, G. Chouteau, P. Lejay, P. Radaelli, C. Chaillout. 1998-03-05. Magnetic and Electric properties of La_{1-delta}MnO_{3}. https://doi.org/10.1103/physrevb.59.1304

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