Magnetoimpedance, magnetoresistance, and magnetic properties of nanometric CMR manganites

摘要

The effects of nanometric grain size ((phi)(velence)14-28 nm) modulation on the behavior of magnetoimpedance (MI), magnetoresistance, and magnetic properties of chemically synthesized a series of single-phase soft ferromagnetic nanocrystalline colossal magnetoresistance La_(0.7)Sr_(0.3)MnO_(3) (LSMO) manganites at room temperature have been reported. From the frequency and magnetic filed dependent MI measurement it is found that the MI percent increases with the increase in nanometric grain size (phi) for this series of samples. This behavior has been explained in the light of classical electrodynamics, which relates this effect with the dependency of skin depth on external magnetic field and applied ac signal frequency. Room temperature low field magnetoresistance (LFMR) study of this series of LSMO nanoparticles has also been carried out for comparison.