Robust kagome electronic structure in the topological quantum magnets <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>X</mml:mi><mml:msub><mml:mi>Mn</mml:mi><mml:mn>6</mml:mn></mml:msub><mml:msub><mml:mi>Sn</mml:mi><mml:mn>6</mml:mn></mml:msub></mml:mrow></mml:math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mo>(</mml:mo><mml:mi>X</mml:mi><mml:mo>=</mml:mo><mml:mi>Dy</mml:mi><mml:mo>,</mml:mo><mml:mi>Tb</mml:mi><mml:mo>,</mml:mo><mml:mi>Gd</mml:mi><mml:mo>,</mml:mo><mml:mi mathvariant="normal">Y</mml:mi><mml:mo>)</mml:mo></mml:mrow></mml:math>
Xu Gu, C. Chen, Wensen Wei, Lingling Gao, Jieyi Liu, Xiaofan Du, Ding Pei, Jingwen Zhou, R. Z. Xu, Zhi-feng Yin, Wenxuan Zhao, Yening Li, Chris Jozwiak, Aaron Bostwick, Eli Rotenberg, D. Backes, L. S. I. Veiga, S. S. Dhesi, T. Hesjedal, G. van der Laan, Haifeng Du, W. J. Jiang, Yunxi Qi, G. Li, Wenyu Shi, Z. K. Liu, Y. L. Chen, Lexian Yang
Abstract
Crystal geometry can greatly influence the emergent properties of quantum materials. As an example, the kagome lattice is an ideal platform to study the rich interplay between topology, magnetism, and electronic correlation. In this work, combining high-resolution angle-resolved photoemission spectroscopy and ab initio calculation, we systematically investigate the electronic structure of $X{\mathrm{Mn}}_{6}{\mathrm{Sn}}_{6}$ $(X=\mathrm{Dy},\mathrm{Tb},\mathrm{Gd},\mathrm{Y})$ family compounds. We observe the Dirac fermion and the flat band arising from the magnetic kagome lattice of Mn atoms. Interestingly, the flat band locates in the same energy region in all compounds studied, regardless of their different magnetic ground states and $4f$ electronic configurations. These observations suggest a robust Mn magnetic kagome lattice across the $X{\mathrm{Mn}}_{6}{\mathrm{Sn}}_{6}$ family, thus providing an ideal platform for the search for, and investigation of, new emergent phenomena in magnetic topological materials.