A generic dual d-band model for interlayer ferromagnetic coupling in a transition-metal doped MnBi 2 Te 4 family of materials
A generic dual d-band model for interlayer ferromagnetic coupling in a transition-metal doped MnBi 2 Te 4 family of materials
复制标题
过渡金属掺杂 MnBi 2 Te 4 系列材料中层间铁磁耦合的通用双 d 带模型
DOI：
10.1039/d2nr03283j
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发表时间：
2022
期刊：
影响因子：
6.7
通讯作者：
Liu, Feng
中科院分区：
文献类型：
--
作者：
Zhang, Huisheng;Zhang, Jingjing;Zhang, Yaling;Yang, Wenjia;Wang, Yingying;Xu, Xiaohong;Liu, Feng
在MnBi2Te4系列材料（mbt）的磁性拓扑绝缘体（TIs）中实现铁磁层间耦合可能为实现高温量子反常霍尔效应（高t QAHE）铺平道路。在这里，我们提出了一个通用的双d波段（DDB）模型来解释过渡金属（TM）掺杂mbt中AFM和FM耦合之间的能量差（ΔE = EAFM−EFM），其中TMs的价电子分为d-t2g和d-eg子带。值得注意的是，DDB表明ΔE普遍由掺杂剂(X)和Mn d-eg/t2波段的相对位置决定。如果ΔEd > 0，那么ΔE >和所需的FM耦合是首选的。这一惊人的简单规律被空穴型3d和4d TM掺杂剂的第一线原理计算证实。值得注意的是，通过应用DDB模型，我们预测了v掺杂Mn2Bi2Te5中的高t QAHE，其中居里温度通过MnTe层的加倍而提高，而掺杂降低的拓扑秩序可以通过应变恢复。
Realization of ferromagnetic (FM) interlayer coupling in magnetic topological insulators (TIs) of the MnBi2Te4 family of materials (MBTs) may pave the way for realizing the high-temperature quantum anomalous Hall effect (high-T QAHE). Here we propose a generic dual d-band (DDB) model to elucidate the energy difference (ΔE = EAFM − EFM) between the AFM and FM coupling in transition-metal (TM)-doped MBTs, where the valence of TMs splits into d-t2g and d-eg sub-bands. Remarkably, the DDB shows that ΔE is universally determined by the relative position of the dopant (X) and Mn d-eg/t2g bands, . If ΔEd > 0, then ΔE > 0 and the desired FM coupling is favored. This surprisingly simple rule is confirmed by first-principles calculations of hole-type 3d and 4d TM dopants. Significantly, by applying the DDB model, we predict the high-T QAHE in the V-doped Mn2Bi2Te5, where the Curie temperature is enhanced by doubling of the MnTe layer, while the topological order mitigated by doping can be restored by strain.