Magnetoelectric and magnetodielectric properties of (1−x)Ba0.6Sr0.4TiO3–(x)La0.7Ca0.3MnO3 composites

We have investigated the magnetoelectric and magnetodielectric properties of (1−x)Ba0.6Sr0.4TiO3–(x)La0.7Ca0.3MnO3 composites, where constituent Ba0.6Sr0.4TiO3 and La0.7Ca0.3MnO3 have nearly the same ferroelectric (TCE∼270K) and ferromagnetic (TCM∼275K) Curie temperatures. Below a percolation-limit sample, i.e., x=0.05x=0.05, we have observed a decrease of electrical polarization and an increase of dielectric constant with strong frequency dependences near TCMTCM when we turn on the magnet. On the other hand, we have observed little change of electrical polarization and a decrease of dielectric constant without frequency dependences at 10 K. We have attributed the observed magnetoelectric and magnetodielectric properties to the extrinsic magnetoresistance origin near TCMTCM and to the strain-induced magnetoelectric coupling at 10 K.