ELECTRICAL RESISTIVITY AND AC SUSCEPTIBILITY STUDIES IN Sr1-xLaxMnO3
Electron-doped Sr 1-x La x MnO 3(0≤x≤0.50) and hole-doped (x=0.70 and 0.82) samples have been prepared by solid state route. X-ray diffraction patterns could be refined using P63 space group for x≤0.30 and [Formula: see text] space group for x≥0.40. Temperature variation of AC susceptibility measurements show that all the electron-doped materials exhibit paramagnetic to ferromagnetic transitions with the transition temperatures ranging from 375 to 393 K, followed by low temperature antiferromagnetic transitions. The ferromagnetic maximum susceptibility is found to increase systematically with La doping, i.e. with increase in Mn 3+ ions. The high temperature resistivity data could be analyzed using the Mott-variable range hopping model. The hole-doped materials exhibit ferromagnetic to paramagnetic transition.