Increase of the dielectric constant near a magnetic phase transition in La0.5Ca0.5MnO3

PABLO M. BOTTA; JORGE MIRA; ALFONSO FONDADO; JOSÉ RIVAS

MATERIALS LETTERS

Año: 2007 vol. 51 p. 150 - 152

0167-577X

The dielectric response of polycrystalline La0.5Ca0.5MnO3 as a function of frequency and temperature was studied. The semiconducting nature of this oxide gave rise to very high dielectric constant values, which were mainly attributed to interfacial polarization (grain boundaries and contacts sample-electrode). However, an increase of the permittivity at temperatures close to a magnetic phase transition suggests the contribution of intrinsic effects to the observed high dielectric constants.