Magnetic after-effect in manganite films

M. SIRENA; L.B. STEREN; J. GUIMPEL

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

ELSEVIER SCIENCE BV

Año: 2001 vol. 226 p. 847 - 848

0304-8853

The time dependence of the magnetic and transport properties on La0.6Sr0.4MnO3 films and bulk samples has been studied through magnetization and resistivity measurements. A magnetic after-effect has been observed in all samples. At low temperatures, the low-field magnetization, can be described by the function . The resistivity increases logarithmically in the same temperature range, indicating the evolution of the sample to a more disordered state. Above a characteristic temperature, this behaviour is reversed and an increase of the magnetization with time is observed. The relaxation parameters depend on the bulk or films character of the samples. In the latter case, a dependence on the film thickness was found. A direct correlation between the time dependence of the resistivity and magnetization curves in manganite compounds was found.