We have prepared a 20% Pr doped Sm_0.55Sr_0.45MnO₃ sample by using the solid-state reaction and studied the magnetic and electrical properties. Arrott plots confirm the occurrence of a first-order phase transition. All the signatures of the FM first-order transition disappear above a critical magnetic field. Based on dc-electrical conductivity, a metal semi-conductor transition has been observed at T_M-Sc = 180 K. Temperature-dependent conductivity measurement has been carried out to probe the electrical conduction mechanism, which revealed the change of conduction mechanism from the variable range hopping to the small polaron hopping around 180 K. The temperature dependence of ε’ indicates a dielectric anomaly, implying a possible ME coupling in the vicinity of FM transition. The modulus spectra and complex impedance of the reported sample undoubtedly showed the non-Debye type relaxation process. We have obtained different activation energies values calculated from the conduction and relaxation mechanism. An electrical equivalent circuit model was suggested to explain the impedance contributions.

我们准备了20％Pr掺杂的Sm _0.55 Sr _{0 。}利用固相反应对₄₅ MnO ₃样品进行了研究，研究了磁性和电学性质。阿罗特图确认了一阶相变的发生。FM一阶跃迁的所有信号在临界磁场上方消失。基于直流电导率，在T _M-Sc处观察到金属半导体跃迁 = 180K。已经进行了随温度变化的电导率测量，以探测电导率机制，揭示了电导率机制从180 K附近的可变范围跳变到小极化子跳变。ε'的温度依赖性表示电介质异常，暗示在FM过渡附近可能存在ME耦合。所报告样品的模量谱和复阻抗无疑显示了非德拜型弛豫过程。我们已经获得了根据传导和弛豫机制计算出的不同活化能值。建议使用等效电路模型来解释阻抗贡献。