论文标题
纳米晶状体的物理特性SM $ _2 $ comno $ _6 $：结构，磁性，旋转phonon耦合和介电研究
Physical Properties of Nano-crystalline Sm$_2$CoMnO$_6$: structure, magnetism, spin-phonon coupling and dielectric study
论文作者
论文摘要
已经研究了SM $ _2 $ comno $ _6 $的结构，磁性和介电特性。 X射线衍射和Rietveld分析表明，样品在单斜结构中以\ textit {p2 $ _1 $/n}空间组结晶。磁研究表明，该样品在$ t_c $ $ \ sim $ 148 K和低温订购sm $^{3+} $ iments $ t_c $ \ sim $ 148 K附近经历了磁磁到铁磁相变。温度依赖性拉曼研究显示了该材料中存在的旋转偶联。 SM $ _2 $ comno $ _6 $的介电响应显示强频依赖性，具有较大的分散和较大的介电常数。在阻抗光谱中发现了与理想Debye模型偏离的。此外，从切线损失和复杂阻抗中获得的活化能表明，松弛过程是由于电子跳跃引起的。已经研究了交流电导率以了解传导机制。交流电导率的详细分析表明，电荷的量子机械隧穿与传导机制有关。从交流电导率测量获得的指数证实了SM $ _2 $ comno $ _6 $的非debye的性质。
Structural, magnetic, and dielectric properties of Sm$_2$CoMnO$_6$ have been studied. X-ray diffraction and Rietveld analysis show that the sample crystallizes in the monoclinic structure with \textit{P2$_1$/n} space group. Magnetic study shows that the sample undergoes a paramagnetic to ferromagnetic phase transition around $T_c$ $\sim$148 K and a low-temperature ordering of Sm$^{3+}$ moments. Temperature-dependent Raman study shows spin-phonon coupling present in this material. Dielectric response of Sm$_2$CoMnO$_6$ shows strong frequency dependence with large dispersion and large dielectric constant. Deviated from ideal Debye's model is found in impedance spectroscopy. Further, the activation energy obtained from tangent loss and complex impedance suggests that the relaxation process is due to electron hopping. AC conductivity has been studied to understand the conduction mechanism. The detailed analysis of AC conductivity shows that quantum mechanical tunneling of charges is involved in the conduction mechanism. The exponent obtained from AC conductivity measurements confirms the non-Debye's nature of Sm$_2$CoMnO$_6$.
