First-Order Studies of Nanometric Biferroic

• 作者: M. A. Ahmed N. G. Imam U. Seddik
• 来源期刊: 凝固态物理国际期刊(英文)
• 学科: 化学
• 关键词: Biferroic NANOCOMPOSITE Nickel-Zinc FERRITE BARIUM TITANATE Dielectric HYSTERESIS FIRST-ORDER Transition
• 年，卷（期）: 2012,（2）
• 页码范围: 66-74
• 页数: 9页
• 分类号: O6

摘要

Magnetoelectric biferroic nanocomposite with composition 0.5Ni0.5Zn0.5Fe2O4 + 0.5BaTiO3 was synthesized by ceramic technique. The structural and electrical characterizations of the investigated nanocomposite are discussed and reported. The formation of nanosized composite with two separate phases was confirmed by X-ray diffraction, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The variation of dielectric constant (ε'), dielectric loss factor (ε') and the ac conductivity (σac) of 0.5Ni0.5Zn0.5Fe2O4 + 0.5BaTiO3 was investigated as a function of both frequency and temperature. Thermal hysteresis (first-order transition) was obtained during heating (300 - 830 K) and cooling runs (830 - 300 K). The exact transition temperature and the amount area of the thermal hysteresis depend on applied ac electric field. The delay (lagging) time between heating and cooling processes was esti-mated from the hysteresis loop area versus frequency. The conduction mechanism in the investigated samples was explained according to different models. This study enhances the use of this prepared system in memory applications.