| CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES |
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Flat Band and $\mathbb{Z}_2$ Topology of Kagome Metal CsTi$_{3}$Bi$_{5}$ |
| Yuan Wang1†, Yixuan Liu1†, Zhanyang Hao1†, Wenjing Cheng1†, Junze Deng2†, Yuxin Wang2, Yuhao Gu2, Xiao-Ming Ma1, Hongtao Rong1, Fayuan Zhang1, Shu Guo1, Chengcheng Zhang1, Zhicheng Jiang3, Yichen Yang3, Wanling Liu3, Qi Jiang3, Zhengtai Liu3, Mao Ye3, Dawei Shen3, Yi Liu4, Shengtao Cui4, Le Wang1, Cai Liu1, Junhao Lin1, Ying Liu1, Yongqing Cai1*, Jinlong Zhu1, Chaoyu Chen1*, and Jia-Wei Mei1* |
1Shenzhen Institute for Quantum Science and Engineering (SIQSE) and Department of Physics, Southern University of Science and Technology (SUSTech), Shenzhen 518055, China
2Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
3State Key Laboratory of Functional Materials for Informatics and Center for Excellence in Superconducting Electronics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China
4National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China
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| Cite this article: |
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Yuan Wang, Yixuan Liu, Zhanyang Hao et al 2023 Chin. Phys. Lett. 40 037102 |
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Abstract The simple kagome-lattice band structure possesses Dirac cones, flat band, and saddle point with van Hove singularities in the electronic density of states, facilitating the emergence of various electronic orders. Here we report a titanium-based kagome metal CsTi$_{3}$Bi$_{5}$ where titanium atoms form a kagome network, resembling its isostructural compound CsV$_{3}$Sb$_{5}$. Thermodynamic properties including the magnetization, resistance, and heat capacity reveal the conventional Fermi liquid behavior in the kagome metal CsTi$_{3}$Bi$_{5}$ and no signature of superconducting or charge density wave (CDW) transition anomaly down to 85 mK. Systematic angle-resolved photoemission spectroscopy measurements reveal multiple bands crossing the Fermi level, consistent with the first-principles calculations. The flat band formed by the destructive interference of hopping in the kagome lattice is observed directly. Compared to CsV$_{3}$Sb$_{5}$, the van Hove singularities are pushed far away above the Fermi level in CsTi$_{3}$Bi$_{5}$, in line with the absence of CDW. Furthermore, the first-principles calculations identify the nontrivial $\mathbb{Z}_2$ topological properties for those bands crossing the Fermi level, accompanied by several local band inversions. Our results suppose CsTi$_{3}$Bi$_{5}$ as a complementary platform to explore the superconductivity and nontrivial band topology.
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Received: 06 January 2023
Editors' Suggestion
Published: 02 March 2023
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| PACS: |
74.25.Jb
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(Electronic structure (photoemission, etc.))
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71.20.-6
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71.18.+y
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(Fermi surface: calculations and measurements; effective mass, g factor)
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73.20.At
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(Surface states, band structure, electron density of states)
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| [1] | Fu L and Kane C L 2008 Phys. Rev. Lett. 100 096407 |
| [2] | Qi X L and Zhang S C 2011 Rev. Mod. Phys. 83 1057 |
| [3] | Guo H M and Franz M 2009 Phys. Rev. B 80 113102 |
| [4] | Tang E, Mei J W, and Wen X G 2011 Phys. Rev. Lett. 106 236802 |
| [5] | Yu S L and Li J X 1952 Phys. Rev. B 85 144402 |
| [6] | Kiesel M L, Platt C, and Thomale R 2013 Phys. Rev. Lett. 110 126405 |
| [7] | Wang W S, Li Z Z, Xiang Y Y, and Wang Q H 1952 Phys. Rev. B 87 115135 |
| [8] | Ye L D, Kang M G, Liu J W et al. 2018 Nature 555 638 |
| [9] | Li M, Wang Q, Wang G et al. 2021 Nat. Commun. 12 3129 |
| [10] | Kang M G, Ye L D, Fang S et al. 2020 Nat. Mater. 19 163 |
| [11] | Kang M G, Fang S, Ye L D et al. 2020 Nat. Commun. 11 4004 |
| [12] | Yin J X, Ma W L, Cochran T A et al. 2020 Nature 583 533 |
| [13] | Liu E K, Sun Y, Kumar N et al. 2018 Nat. Phys. 14 1125 |
| [14] | Nakatsuji S, Kiyohara N, and Higo T 2015 Nature 527 212 |
| [15] | Ortiz B R, Teicher S M L, Hu Y et al. 2020 Phys. Rev. Lett. 125 247002 |
| [16] | Ortiz B R, Sarte P M, Kenney E M, Graf M J, Teicher S M L, Seshadri R, and Wilson S D 2021 Phys. Rev. Mater. 5 034801 |
| [17] | Yin Q, Tu Z, Gong C, Fu Y, Yan S, and Lei H 2021 Chin. Phys. Lett. 38 037403 |
| [18] | Yang S Y, Wang Y J, Ortiz B R et al. 2020 Sci. Adv. 6 eabb6003 |
| [19] | Yu F H, Wu T, Wang Z Y, Lei B, Zhuo W Z, Ying J J, and Chen X H 2021 Phys. Rev. B 104 L041103 |
| [20] | Chen H, Yang H, Hu B et al. 2021 Nature 599 222 |
| [21] | Jiang Y X, Yin J X, Denner M M et al. 2021 Nat. Mater. 20 1353 |
| [22] | Nie L P, Sun K L, Ma W R et al. 2022 Nature 604 59 |
| [23] | Xiang Y, Li Q, Li Y, Xie W, Yang H, Wang Z, Yao Y, and Wen H H 2021 Nat. Commun. 12 6727 |
| [24] | Xu Y S, Ni Z L, Liu Y Z, Ortiz B R, Deng Q W, Wilson S D, Yan B H, Balents L, and Wu L 2022 Nat. Phys. 18 1470 |
| [25] | Yu L, Wang C, Zhang Y et al. 2021 arXiv:2107.10714 [cond-mat.supr-con] |
| [26] | Mielke C, Das D, Yin J X et al. 2022 Nature 602 245 |
| [27] | Feng X L, Jiang K, Wang Z Q, and Hu J P 2021 Sci. Bull. 66 1384 |
| [28] | Jiang Y, Yu Z, Wang Y, Lu T, Meng S, Jiang K, and Liu M 2022 Chin. Phys. Lett. 39 047402 |
| [29] | Yang H, Zhao Z, Yi X W et al. 2022 arXiv:2209.03840 [cond-mat.supr-con] |
| [30] | Werhahn D, Ortiz B R, Hay A K, Wilson S D, Seshadri R, and Johrendt D 2022 Z. Naturforsch. B 77 757 |
| [31] | Li Y F, Wang E Y, Zhu X Y, and Wen H H 2017 Phys. Rev. B 95 024510 |
| [32] | Cai Y, Wang Y, Hao Z et al. 2021 arXiv:2109.12778 [cond-mat.supr-con] |
| [33] | Hu Y, Teicher S M L, Ortiz B R et al. 2022 Sci. Bull. 67 495 |
| [34] | Yang J, Xie Y, Zhao Z et al. 2022 arXiv:2212.04447 [cond-mat.supr-con] |
| [35] | Liu B, Kuang M, Luo Y et al. 2022 arXiv:2212.04460 [cond-mat.str-el] |
| [36] | Jiang Z, Liu Z, Ma H et al. 2022 arXiv:2212.02399 [cond-mat.str-el] |
| [37] | Hu Y, Le C, Zhao Z et al. 2022 arXiv:2212.07958 [cond-mat.supr-con] |
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