Quantum Hall effect in a bulk antiferromagnet EuMnBi2 with magnetically confined two-dimensional Dirac fermions.
Quantum Hall effect in a bulk antiferromagnet EuMnBi2 with magnetically confined two-dimensional Dirac fermions.
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DOI：
10.1126/sciadv.1501117
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发表时间：
2016-01
期刊：
影响因子：
13.6
通讯作者：
Ishiwata S
中科院分区：
文献类型：
--
作者：
Masuda H;Sakai H;Tokunaga M;Yamasaki Y;Miyake A;Shiogai J;Nakamura S;Awaji S;Tsukazaki A;Nakao H;Murakami Y;Arima TH;Tokura Y;Ishiwata S
准二维狄拉克费米子的量子输运在很大程度上受层状磁体中磁序的控制。对于自旋电子技术的创新，狄拉克材料，其中低能激发被描述为相对论狄拉克费米子，是最有前途的系统之一，因为与极高的迁移率相关的迷人的磁输运。为了将狄拉克费米子引入自旋电子的应用，人们希望在很大程度上通过固体中的磁序来操纵它们的量子输运现象。我们报道了层状反铁磁体EuMnBi2中的体相半整数量子霍尔效应，其中场可控的Eu磁序显著抑制了Bi层与Dirac费米子之间的层间耦合。除了10,000 cm~2/V以上的S的高迁移率外，即使在块状磁体中，由于自旋和谷简并的解除而引起的朗道能级分裂也是明显的。这些结果将为磁功能化狄拉克材料的工程化铺平道路。
Quantum transport of quasi–two-dimensional Dirac fermions is largely controlled by magnetic order in a layered magnet. For the innovation of spintronic technologies, Dirac materials, in which low-energy excitation is described as relativistic Dirac fermions, are one of the most promising systems because of the fascinating magnetotransport associated with extremely high mobility. To incorporate Dirac fermions into spintronic applications, their quantum transport phenomena are desired to be manipulated to a large extent by magnetic order in a solid. We report a bulk half-integer quantum Hall effect in a layered antiferromagnet EuMnBi2, in which field-controllable Eu magnetic order significantly suppresses the interlayer coupling between the Bi layers with Dirac fermions. In addition to the high mobility of more than 10,000 cm2/V s, Landau level splittings presumably due to the lifting of spin and valley degeneracy are noticeable even in a bulk magnet. These results will pave a route to the engineering of magnetically functionalized Dirac materials.