The effect of particle size on the structural, magnetic and electrical properties of La0.9Ba0.1MNO3 manganite samples

Abstract

ABSTRACTIn this work, the magnetic and transport properties of micro and nanometer-sized samples of La0.9Ba0.1MnO3 manganite have been studied. The temperature variation of ac susceptibility of the nanometer-sized sample shows one transition at high temperature (265 K). On the contrary, the ac susceptibility of the micrometer-sized sample shows two transitions with a high-temperature transition occurring at 240 K and low-temperature transition around 100 K. The high-temperature transition corresponds to the paramagnetic-ferromagnetic (PM–FM) transition (Tc) and is independent of frequency, while the low-temperature transition is frequency-dependent and shifts toward high temperatures by increasing frequency. The different magnetic behavior for two samples may be understood on the basis of crystalline homogeneity. The competition between FM double exchange and antiferromagnetic superexchange component in the micrometer-sized sample leads to the cluster glass state at low temperatures. The magnetotransport data further supports the obtained results from magnetic measurements.