J. Phys. IV France 08 (1998) Pr2-359-Pr2-362
Magnetic and conductive properties of La0.5Pb0.5MnO3E. Rozenberg1, G. Gorodetsky2, N. Froumin1, J. Pelleg1, M. Polak1, I. Felner3 and B.K. Chaudhuri4
1 Department of Materials Enginnering, Ben-Gurion University of the Negev, P.O. Box 653, 84105 Beer-Sheva, Israel
2 Department of Physics, Ben-Gurion University of the Negev, P.O. Box 653, 84105 Beer-Sheva, Israel
3 Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
4 Solid State Physics Department, Association for the Cultivation of Science, Calcutta 700032, India
The magnetic and conductive properties of polycrystalline La0.5Pb0.5MnO3 containing ~13at.% of a second phase PB3Mn6O13. were investigated. The studies reported include measurements of magnetization, electrical resistivity and magnetoresistance, in a temperature range 10 ÷ 400 K and at applied magnetic fields up to 5 Tesla. It was found that the sample exhibits a ferromagnetic ordering with relatively low coercive field at room temperature. Measurements of field-cooled and reversed-field-cooled magnetization support models of coexisting magnetic phases in ferromagnetic La-based manganites. The resistivity measured eshibits a maximum at ~ 230 K and a broad shallow minimum at ~ 20+25 K. These features are also attnbuted to the temperature dependence of the magnctic inhomogeneities. Measurcments of magnetoresistance show a characteristic giant effect at low temperatures.
© EDP Sciences 1998