论文标题
抗铁磁性和莫特状态的偶性伴侣在旋转式耦合的SR2IRO4：SR2IR1-XMXO4的研究（M = Fe或Co）
Fortuitous partners of antiferromagnetic and Mott states in spin-orbit-coupled Sr2IrO4: A study of Sr2Ir1-xMxO4 (M=Fe or Co)
论文作者
论文摘要
SR2IRO4是一种原型自旋轨道耦合莫特绝缘子，其抗磁性状态低于240K。在这里，我们报告了有关SR2IR1-XFEXO4（0 <x <0.32）和SR2IR1-XCOXO4（0 <x <0.32）的单晶的研究结果。 Fe兴奋剂保留了抗磁性状态，但同时沉淀出出现的金属状态，而兴奋剂则导致抗铁磁性和莫特状态的迅速崩溃，从而产生了限制的金属状态，具有较大的基础电阻的明显线性，直至700 k。在高自旋状态下的s = 1和Co4+（3dd5）离子分别在SR2IRO4中代替IR4+（5d5）离子。随着掺杂的增加，有效的磁矩紧密跟踪Néel温度，这表明掺杂剂的自旋态主要决定掺杂的SR2IRO4中的磁性。此外，所有相关特性在内的所有相关特性，包括电荷载体密度（例如1028/m3），Sommerfeld系数（例如19 MJ/Mole K2）和Wilson比率（例如2.6），始终证明了在两个系统中既有构成且在构造中都具有较高且高度相关的金属状态和高度相关的结构。这项研究强烈表明，抗铁磁和莫特在SR2IRO4中仅以偶然的方式共存。
Sr2IrO4 is an archetypal spin-orbit-coupled Mott insulator with an antiferromagnetic state below 240 K. Here we report results of our study on single crystals of Sr2Ir1-xFexO4 (0<x<0.32) and Sr2Ir1-xCoxO4 (0<x<0.22). Fe doping retains the antiferromagnetic state but simultaneously precipitates an emergent metallic state whereas Co doping causes a rapid collapse of both the antiferromagnetic and Mott states, giving rise to a confined metallic state featuring a pronounced linearity of the basal-plane resistivity up to 700 K. The results indicate tetravalent Fe4+(3d4) ions in the intermediate spin state with S=1 and Co4+(3d5) ions in the high spin state with S=5/2 substituting for Ir4+(5d5) ions in Sr2IrO4, respectively. The effective magnetic moment closely tracks the Néel temperature as doping increases, suggesting that the spin state of the dopant predominately determines the magnetic properties in doped Sr2IrO4. Furthermore, all relevant properties including charge-carrier density (e.g., 1028/m3), Sommerfeld coefficient (e.g., 19 mJ/mole K2) and Wilson ratio (e.g., 2.6), consistently demonstrates a metallic state that is both robust and highly correlated in the two systems, arising from the percolation of bound states and the weakening of structural distortions. This study strongly suggests that the antiferromagnetic and Mott states merely coexist in a fortuitous manner in Sr2IrO4.
