%0 Journal Article %1 gao2021layer %A Gao, Anyuan %A Liu, Yu-Fei %A Hu, Chaowei %A Qiu, Jian-Xiang %A Tzschaschel, Christian %A Ghosh, Barun %A Ho, Sheng-Chin %A Bérubé, Damien %A Chen, Rui %A Sun, Haipeng %A Zhang, Zhaowei %A Zhang, Xin-Yue %A Wang, Yu-Xuan %A Wang, Naizhou %A Huang, Zumeng %A Felser, Claudia %A Agarwal, Amit %A Ding, Thomas %A Tien, Hung-Ju %A Akey, Austin %A Gardener, Jules %A Singh, Bahadur %A Watanabe, Kenji %A Taniguchi, Takashi %A Burch, Kenneth S. %A Bell, David C. %A Zhou, Brian B. %A Gao, Weibo %A Lu, Hai-Zhou %A Bansil, Arun %A Lin, Hsin %A Chang, Tay-Rong %A Fu, Liang %A Ma, Qiong %A Ni, Ni %A Xu, Su-Yang %D 2021 %J Nature %K a b %N 7868 %P 521--525 %R 10.1038/s41586-021-03679-w %T Layer Hall effect in a 2D topological axion antiferromagnet %U https://doi.org/10.1038/s41586-021-03679-w %V 595 %X Whereas ferromagnets have been known and used for millennia, antiferromagnets were only discovered in the 1930s1. At large scale, because of the absence of global magnetization, antiferromagnets may seem to behave like any non-magnetic material. At the microscopic level, however, the opposite alignment of spins forms a rich internal structure. In topological antiferromagnets, this internal structure leads to the possibility that the property known as the Berry phase can acquire distinct spatial textures2,3. Here we study this possibility in an antiferromagnetic axion insulator—even-layered, two-dimensional MnBi2Te4—in which spatial degrees of freedom correspond to different layers. We observe a type of Hall effect—the layer Hall effect—in which electrons from the top and bottom layers spontaneously deflect in opposite directions. Specifically, under zero electric field, even-layered MnBi2Te4 shows no anomalous Hall effect. However, applying an electric field leads to the emergence of a large, layer-polarized anomalous Hall effect of about 0.5e2/h (where e is the electron charge and h is Planck’s constant). This layer Hall effect uncovers an unusual layer-locked Berry curvature, which serves to characterize the axion insulator state. Moreover, we find that the layer-locked Berry curvature can be manipulated by the axion field formed from the dot product of the electric and magnetic field vectors. Our results offer new pathways to detect and manipulate the internal spatial structure of fully compensated topological antiferromagnets4–9. The layer-locked Berry curvature represents a first step towards spatial engineering of the Berry phase through effects such as layer-specific moiré potential.

@article{gao2021layer, abstract = {Whereas ferromagnets have been known and used for millennia, antiferromagnets were only discovered in the 1930s1. At large scale, because of the absence of global magnetization, antiferromagnets may seem to behave like any non-magnetic material. At the microscopic level, however, the opposite alignment of spins forms a rich internal structure. In topological antiferromagnets, this internal structure leads to the possibility that the property known as the Berry phase can acquire distinct spatial textures2,3. Here we study this possibility in an antiferromagnetic axion insulator—even-layered, two-dimensional MnBi2Te4—in which spatial degrees of freedom correspond to different layers. We observe a type of Hall effect—the layer Hall effect—in which electrons from the top and bottom layers spontaneously deflect in opposite directions. Specifically, under zero electric field, even-layered MnBi2Te4 shows no anomalous Hall effect. However, applying an electric field leads to the emergence of a large, layer-polarized anomalous Hall effect of about 0.5e2/h (where e is the electron charge and h is Planck’s constant). This layer Hall effect uncovers an unusual layer-locked Berry curvature, which serves to characterize the axion insulator state. Moreover, we find that the layer-locked Berry curvature can be manipulated by the axion field formed from the dot product of the electric and magnetic field vectors. Our results offer new pathways to detect and manipulate the internal spatial structure of fully compensated topological antiferromagnets4–9. The layer-locked Berry curvature represents a first step towards spatial engineering of the Berry phase through effects such as layer-specific moiré potential.}, added-at = {2023-11-16T13:44:53.000+0100}, author = {Gao, Anyuan and Liu, Yu-Fei and Hu, Chaowei and Qiu, Jian-Xiang and Tzschaschel, Christian and Ghosh, Barun and Ho, Sheng-Chin and Bérubé, Damien and Chen, Rui and Sun, Haipeng and Zhang, Zhaowei and Zhang, Xin-Yue and Wang, Yu-Xuan and Wang, Naizhou and Huang, Zumeng and Felser, Claudia and Agarwal, Amit and Ding, Thomas and Tien, Hung-Ju and Akey, Austin and Gardener, Jules and Singh, Bahadur and Watanabe, Kenji and Taniguchi, Takashi and Burch, Kenneth S. and Bell, David C. and Zhou, Brian B. and Gao, Weibo and Lu, Hai-Zhou and Bansil, Arun and Lin, Hsin and Chang, Tay-Rong and Fu, Liang and Ma, Qiong and Ni, Ni and Xu, Su-Yang}, biburl = {https://www.bibsonomy.org/bibtex/21e963168562d8ca90917eb035b575947/ctqmat}, day = 21, doi = {10.1038/s41586-021-03679-w}, interhash = {a4bc1be9f4748fd6acefaa9f22665c82}, intrahash = {1e963168562d8ca90917eb035b575947}, issn = {14764687}, journal = {Nature}, keywords = {a b}, month = {07}, number = 7868, pages = {521--525}, refid = {Gao2021}, timestamp = {2023-11-16T13:44:53.000+0100}, title = {Layer Hall effect in a 2D topological axion antiferromagnet}, url = {https://doi.org/10.1038/s41586-021-03679-w}, volume = 595, year = 2021 }