Electrical and Magnetoelectric Properties of(Y)Li_0.5Ni_0.7Zn_0.05Fe_2O_4 + (1-Y)Ba_0.5Sr_0.5TiO_3 Magnetoelectric Composites

摘要

(y) Li_0.5Ni_0.7Zn_0.05Fe_2O_4 + (1-y) Ba_0.5Sr_0.5TiO_3 magnetoelectric composites with y = 0.1, 0.3 and 0.5 were prepared by a conventional standard double sintering ceramic technique. X-ray diffraction analysis confirmed the phase formation of ferrite, ferroelectric and their composites. logρdc Vs 1/T graphs reveal that the dc resistivity decreases with increasing temperature exhibiting semiconductor behavior. The plots of logσ_(ac) Vs logω~2 are almost linear indicating that the conductivity increases with increase in frequency i.e. conductivity in the composites is due to small poloron hopping. Dielectric constant (ε) and dielectric loss (tan δ) were studied as a function of frequency in the range 100Hz-1MHz which reveal the normal dielectric behavior except the composite with y = 0.1 and as a function of temperature at four fixed frequencies (i.e. 100Hz, 1KHz, 10KHz, 100KHz). ME voltage coefficient decreases with increase in ferrite content and was observed to be maximum of about 7.495 mV/cmOe for S_1 i.e. (0.1) Li_(0.5)Ni_(0.7)Zn_(0.05)Fe_2O_4 + (0.9) Ba_(0.5)Sr_(0.5)TiO_3 composite.