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

The magnetic phase diagram of $La_{1-\delta}MnO_{3}$ powdered samples have been studied as a function of $\delta $ in the low doping range $(\delta <0.1)$. $La_{0.97}MnO_{3}$ has a canted magnetic structure at low temperature $(\theta \simeq 130\QTR{group}{{}^{\circ}})$. Above $T_{C}=118K$, it becomes a paramagnet with a huge effective magnetic moment, $\mu_{eff}=6.0\mu_{B}$, 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 $\delta $ is increased to $\delta =0.09$, the system becomes fully ferromagnetic below $170K$ but remains insulating.