Abstract We report a finding of two transport regimes in multiferroic BiFeO3 nanoparticles, which correspond to variable range hopping (VRH) mechanisms. Switch between the two regimes coincides with the transition between antiferromagnetic (AF) and paramagnetic (PM) phase. At low temperatures, it was found that temperature dependence of indirectly extracted resistivity is consistent with Efros-Shklovskii mechanism. As with high temperatures, data fit favourably to Mott VRH theory. Estimated resistivity value of ~ 350mΩcm violates the Mott-Ioffe-Regel criterion, corroborating that the transport does not proceed through conduction bands. Conductivity was probed noninvasively via Raman contactless setup and studied as a function of temperature.

中文翻译：

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通过拉曼光谱探测 BiFeO3 纳米粒子中的电荷载流子传输机制

摘要 我们报告了多铁性 BiFeO3 纳米粒子中两种传输机制的发现，它们对应于可变距离跳跃 (VRH) 机制。两种状态之间的切换与反铁磁 (AF) 和顺磁 (PM) 相之间的转变一致。在低温下，发现间接提取电阻率的温度依赖性与 Efros-Shklovskii 机制一致。与高温一样，数据符合莫特 VRH 理论。~ 350mΩcm 的估计电阻率值违反了 Mott-Ioffe-Regel 标准，证实了传输不会通过导带进行。通过拉曼非接触式装置无创地探测电导率，并作为温度的函数进行研究。