Magnetic and Dielectric Properties of (1 – x)BiFeO3–xYMnO3 Multiferroics

Resumo

Magnetic hysteresis loops obtained in the fields from 0 to ±2.5 kOe and dielectric permittivity ε (at 1 kHz, 1 MHz, and 8.3 GHz) of (1 – x)BiFeO₃–xYMnO₃ composite multiferroics (0 ≤ x ≤ 0.5) were studied. Ceramic samples of solid solutions were made by the nitrate process. Compositions (1 – x)BiFeO₃–xYMnO₃ with 0.1 ≤ x ≤ 0.5 were found to be soft ferromagnetic materials sensitive to weak magnetic fields. Coercive field H_c is about 20–32 Oe for these samples. The maximal magnetization was observed in the sample having x = 0.35. For the samples with 0 ≤ x ≤ 0.4 at T = 300 K, the permittivity was ε ~ 17.6–248.6 at the frequency of 1 kHz, 7.8–63.2 at 1 MHz, and 4 ± 0.3 at 8.3 GHz.