Abstract The structural, magnetic, electrical, magneto-dielectric and relaxor characteristics of 0.8BiFeO3-0.2Ba0·8Sr0·2TiO3 sample have been investigated. The XRD analysis explains that the sample possesses a rhombohedral crystal structure with an R3c space group. The sample has been observed to exhibit mixed magnetic ordering (comprising antiferromagnetic and ferromagnetic domains) with a magnetic transition temperature (TM) ≈ 556 K. The dielectric relaxation has been observed to be of non-Debye nature for all measuring temperatures (543 K–813 K). An anomalous dielectric, as well as relaxor behavior with dielectric constant (e׳) peaking between 586 K–609 K for frequency varying from 2999 Hz to 99999 Hz, has also been observed. The sample exhibits positive magnetoelectric coupling with the highest magnetocapacitance (MC) value of 6.12% at 5 kHz. The ac conductivity obeys Universal Jonscher's Power law. The frequency dependence of ac conductivity at two different temperature regions follows the small polaron tunneling (NSPT) model and correlated barrier hopping model (CBH) model.

中文翻译：

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0.8BiFeO3-0.2Ba0·8Sr0·2TiO3固溶体中磁、电、磁介电特性及介电弛豫的研究

摘要 研究了0.8BiFeO3-0.2Ba0·8Sr0·2TiO3样品的结构、磁、电、磁介电和弛豫特性。XRD 分析说明该样品具有菱形晶体结构和 R3c 空间群。已观察到样品表现出混合磁有序（包括反铁磁域和铁磁域），磁转变温度 (TM) ≈ 556 K。已观察到介电弛豫在所有测量温度 (543 K– 813 K）。还观察到异常电介质以及介电常数 (e׳) 在 586 K–609 K 之间达到峰值的弛豫行为，频率从 2999 Hz 到 99999 Hz。该样品表现出正磁电耦合，在 5 kHz 时具有 6.12% 的最高磁电容 (MC) 值。交流电导率遵循通用 Jonscher 幂律。交流电导率在两个不同温度区域的频率依赖性遵循小极化子隧穿 (NSPT) 模型和相关势垒跳跃模型 (CBH) 模型。