论文标题
增强的磁性和抑制了由ca $ _ {1-x} $ y $ _ $ _ {x} $ mnreo $ _6 $的电子掺杂引起的磁弹性耦合
Enhanced magnetism and suppressed magnetoelastic coupling induced by electron doping in Ca$_{1-x}$Y$_{x}$MnReO$_6$
论文作者
论文摘要
CA $ _2 $ MNREO $ _6 $ Double Perovskite是一种带有异国情调磁性特性的旋转轨道辅助的Mott绝缘子，其中包括很大程度上的非电流Mn $^{2+} $旋转布置，并且几乎是这种螺旋的旋转耦合和几乎是正交的耦合，并且较小的Re $ 5D $ 5D $ $ 5D $磁性磁性磁性磁性磁性磁性。在这里，研究了电子掺杂的化合物Ca $ _ {1.7} $ y $ _ {0.3} $ mnreo $ _6 $。中子和X射线粉末衍射证实，在CA地点的Y替代下，在MN和RE位置保持了几乎完全的化学秩序。 X射线吸收测量和对MN-O/RE-O键距离的分析表明，Mn氧化态在+2时保持稳定，而RE在掺杂时降低。电子掺杂将磁性订购温度从$ T_C = 121 $提高到$ 150 $ K，并且还显着增强了MN旋转的铁磁成分，以牺牲在基本温度下的抗磁磁成分（$ T = 3 $ K）。在母体化合物中观察到的$ t_c $的晶格参数异常被电子掺杂抑制。讨论了增强磁性和抑制的磁弹性耦合的可能原因。
The Ca$_2$MnReO$_6$ double perovskite is a spin-orbit-assisted Mott insulator with exotic magnetic properties, including a largely non-collinear Mn$^{2+}$ spin arrangement and nearly orthogonal coupling between such spins and the much smaller Re $5d$ magnetic moments. Here, the electron-doped compound Ca$_{1.7}$Y$_{0.3}$MnReO$_6$ is investigated. Neutron and X-ray powder diffraction confirm that nearly full chemical order is maintained at the Mn and Re sites under the Y substitution at the Ca site. X-ray absorption measurements and an analysis of the Mn-O/Re-O bond distances show that the Mn oxidation state remains stable at +2 whereas Re is reduced upon doping. The electron doping increases the magnetic ordering temperature from $T_c = 121$ to $150$ K and also enhances significantly the ferromagnetic component of the Mn spins at the expense of the antiferromagnetic component at the base temperature ($T=3$ K). The lattice parameter anomalies at $T_c$ observed in the parent compound are suppressed by the electron doping. The possible reasons for the enhanced magnetism and the suppressed magnetoelastic coupling in Ca$_{1.7}$Y$_{0.3}$MnReO$_6$ are discussed.
