کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1606933 1516230 2016 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Complex dielectric and impedance behavior of magnetoelectric Fe2TiO5
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فلزات و آلیاژها
پیش نمایش صفحه اول مقاله
Complex dielectric and impedance behavior of magnetoelectric Fe2TiO5
چکیده انگلیسی


• Fe2TiO5 shows non-Debye type dielectric relaxation around (220–270 K).
• Grain and grain boundary contributions has been analyzed by impedance analysis.
• The ac conduction mechanism is associated with polaron hopping.
• The ac conduction obeys the correlated barrier hopping model.

We have investigated the complex dielectric and impedance properties of magnetoelectric compound Fe2TiO5 (FTO) as a function of temperature (T) and frequency (f) to understand the grain (G) and grain boundary (Gb) contributions to its dielectric response. The temperature and frequency dependent dielectric permittivity (ε′) data shows a sharp increase in permittivity above 200 K accompanied with a frequency dependent peak in tanδ. At T < 175 K, only G contribution dominates even at lower frequency (∼100 Hz), but for T ≥ 175 K, the Gb contribution starts appearing at low frequency. The value of critical frequency distinguishing these two contributions increases with increasing temperature. The observed non-Debye dielectric relaxation follows thermally activated process and is attributed to polaron hopping. Further the frequency dependence of ac conductivity follows the Jonscher's power-law. The temperature dependency of critical exponent ‘s’ shows that the correlated barrier hopping model is appropriate to explain the conductivity mechanism of FTO in the studied temperature regime.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Alloys and Compounds - Volume 663, 5 April 2016, Pages 289–294
نویسندگان
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