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arXiv 1003.0193cond-mat.mtrl-scicond-mat.dis-nncond-mat.mes-hall
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三元Heusler化合物中的可调谐多功能拓扑绝缘体

Tunable Multifunctional Topological Insulators in Ternary Heusler Compounds

S. Chadov, X. -L. Qi, J Kübler, G. H. Fecher, C. Felser, S. -C. Zhang

摘要:

最近,量子自旋霍尔效应(QSH)在二元半导体碲化汞量子阱中被理论预测和实验实现[1-3]。QSH态和拓扑绝缘体是量子物质的新态,在基础凝聚态物理和材料科学中都有重要的应用[1-11]。许多具有C1 b结构的Heusler化合物是三元半导体,它们在结构和电子上与二元半导体相关。Heusler材料的多样性为调整带隙和通过选择具有适当杂化强度(通过晶格参数)和自旋轨道耦合的大小(通过原子电荷)的化合物来设置所需的带反转打开了广泛的可能性。基于第一性原理计算,我们证明了大约50个Heusler化合物显示出类似于HgTe的能带反转。这些零能隙半导体的拓扑状态可以通过施加应变或设计适当的量子阱结构来创建,类似于碲化汞的情况。这些三元零带隙半导体(LnAuPb、LnPdBi、LnPtSb和LnPtBi)中的许多含有稀土元素Ln,其可以实现从超导性(例如,G. [12]第12话,一个人的幸福。G. GdPtBi[13])和重费米子行为(e. G. YbPtBi[14])。这些性质为实现量子化反常霍尔效应和拓扑超导体开辟了新的研究方向。

英文摘要:

Recently the Quantum Spin Hall effect (QSH) was theoretically predicted and experimentally realized in a quantum wells based on binary semiconductor HgTe[1-3]. QSH state and topological insulators are the new states of quantum matter interesting both for fundamental condensed matter physics and material science[1-11]. Many of Heusler compounds with C1b structure are ternary semiconductors which are structurally and electronically related to the binary semiconductors. The diversity of Heusler materials opens wide possibilities for tuning the band gap and setting the desired band inversion by choosing compounds with appropriate hybridization strength (by lattice parameter) and the magnitude of spin-orbit coupling (by the atomic charge). Based on the first-principle calculations we demonstrate that around fifty Heusler compounds show the band inversion similar to HgTe. The topological state in these zero-gap semiconductors can be created by applying strain or by designing an appropriate quantum well structure, similar to the case of HgTe. Many of these ternary zero-gap semiconductors (LnAuPb, LnPdBi, LnPtSb and LnPtBi) contain the rare earth element Ln which can realize additional properties ranging from superconductivity (e. g. LaPtBi[12]) to magnetism (e. g. GdPtBi[13]) and heavy-fermion behavior (e. g. YbPtBi[14]). These properties can open new research directions in realizing the quantized anomalous Hall effect and topological superconductors.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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