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Chin. Phys. B, 2026, Vol. 35(8): 087102    DOI: 10.1088/1674-1056/ae69c6
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Observation of layer-dependent uniaxial charge density wave in a noble metal alloy superconductor β-IrSn4

Xiao Liu(刘潇)1,2,†, Geng Li(李更)1,2,3,†,‡, Shiwei Diao(刁世伟)4,†, Haisen Liu(刘海森)1,2, Zhen Zhao (赵振)1,2, Haitao Yang(杨海涛)1,2,3, Lizhi Zhang(张礼智)4,§, Xiao Lin(林晓)1,¶, and Hong-Jun Gao(高鸿钧)1,2,3
1 School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China;
2 Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
3 Hefei National Laboratory, Hefei 230088, China;
4 Laboratory of Theoretical and Computational Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China
Abstract  The AB$_{4}$-type intermetallic compounds host a wide range of emergent quantum phenomena, providing a fertile platform for exploring the interplay between crystal structure and electronic orders. Among them, $\beta $-IrSn$_{4}$ has recently attracted attention as a noble-metal-based layered superconductor with weak interlayer coupling and type-I superconductivity. However, its electronic states and possible symmetry-breaking orders remain largely unexplored on the atomic scale. Here, we report the observation of a layer-dependent uniaxial charge density wave (CDW) in $\beta $-IrSn$_{4}$ using ultra-low-temperature scanning tunneling microscopy. The charge order appears as stripe-like modulations that break the in-plane $C_{4}$ symmetry, and its orientation rotates by 90$^\circ$ between adjacent layers. Spectroscopy measurements reveal a homogeneous superconducting gap coexisting with the layer-dependent CDW, with no detectable modulation from the charge order. First-principles calculations suggest that interlayer coupling induces the observed anisotropic electronic structure. These results reveal a layer-dependent symmetry-breaking electronic state in $\beta $-IrSn$_{4}$ and highlight the role of interlayer interactions in shaping its electronic properties.
Keywords:  charge density wave      layer-dependent      superconductivity      interlayer coupling  
Received:  08 April 2026      Revised:  26 April 2026      Accepted manuscript online:  07 May 2026
PACS:  71.45.Lr (Charge-density-wave systems)  
  74.55.+v (Tunneling phenomena: single particle tunneling and STM)  
  74.70.-b (Superconducting materials other than cuprates)  
  63.22.Np (Layered systems)  
Fund: Project supported by the National Key Research and Development Program of China (Grant Nos. 2024YFA1207700, 2024YFA1207800, and 2022YFA1204100), the National Natural Science Foundation of China (Grant Nos. 62488201, 61925111, and U23A6015), the CAS Project for Young Scientists in Basic Research (Grant No. YSBR-003), the Youth Innovation Promotion Association (Grant No. 2023005), and the Quantum Science and Technology-National Science and Technology Major Project (Grant No. 2021ZD0302700).
Corresponding Authors:  Geng Li, Lizhi Zhang, Xiao Lin     E-mail:  gengli.iop@iphy.ac.cn;zhanglz@nanoctr.cn;xlin@ucas.ac.cn

Cite this article: 

Xiao Liu(刘潇), Geng Li(李更), Shiwei Diao(刁世伟), Haisen Liu(刘海森), Zhen Zhao (赵振), Haitao Yang(杨海涛), Lizhi Zhang(张礼智), Xiao Lin(林晓), and Hong-Jun Gao(高鸿钧) Observation of layer-dependent uniaxial charge density wave in a noble metal alloy superconductor β-IrSn4 2026 Chin. Phys. B 35 087102

[1] Shen D, Kuo C N, Yang T W, Chen I N, Lue C S and Wang L M 2020 Commun. Mater. 1 56
[2] Zhu W, Song R, Huang J, et al. 2023 Nat. Commun. 14 7012
[3] Ye Y, Song R, Xiao H, Xian G, Guo H, Yang H, Chen H and Gao H J 2024 Nano Lett. 24 13455
[4] Xu C Q, Li B, Zhang L, Pollanen J, Yi X L, Xing X Z, Liu Y, Wang J H, Zhu Z, Shi Z X, Xu X and Ke X 2021 Phys. Rev. B 104 125127
[5] García Talavera P, Moreno J A, Herrera E, Buzdin A I, Bud’ko S L, Canfield P C, Guillamón I and Suderow H 2025 J. Supercond. Nov. Magn. 38 158
[6] Tran V H, Bukowski Z, Wiśniewski P, Tran L M and Zaleski A J 2013 J. Phys.: Condens. Matter 25 155701
[7] Ahmad N, Shimada S, Hasegawa T, Suzuki H, Afzal M A, Nakamura N, Higashinaka R, Matsuda T D and Aoki Y 2024 J. Phys. Soc. Jpn. 93 044706
[8] Speer S, Pershin Y V, Blawat J, Singleton J and Jin R 2026 J. Phys.: Condens. Matter 38 055702
[9] Wu H, Hallas A M, Cai X, Huang J, Oh J S, Loganathan V, Weiland A, McCandless G T, Chan J Y, Mo S K, Lu D, Hashimoto M, Denlinger J, Birgeneau R J, Nevidomskyy A H, Li G, Morosan E and Yi M 2022 npj Quantum Mater. 7 31
[10] Mai T L and Tran V H 2022 RSC Adv. 12 17882
[11] Mun E, Ko H, Miller G J, Samolyuk G D, Bud’ko S L and Canfield P C 2012 Phys. Rev. B 85 035135
[12] Wang Y J, Liang D D, Ge M, Yang J, Gong J X, Luo L, Pi L, ZhuWK, Zhang C J and Zhang Y H 2018 J. Phys.: Condens. Matter 30 155701
[13] Li G, Fu C, Shi W, et al. 2019 Angew. Chem., Int. Ed. 58 13107
[14] Satheasuweatha M N, Mariappan S, Maran T, Kuo C N, Lue C S, Sonachalam A and Joseph B 2025 Phys. Status Solidi RRL 19 2500126
[15] Sahu S, Chen D, Heinsdorf N, Warner A N, Altthaler M, Singh A K, Bonn D A, Burke S A and Hallas A M 2025 Commun. Mater. 6 244
[16] Nordmark E L, Wallner O and Häussermann U 2002 J. Solid State Chem. 168 34
[17] Tranquada J M, Sternlieb B J, Axe J D, Nakamura Y and Uchida S 1995 Nature 375 561
[18] Sipos B, Kusmartseva A F, Akrap A, Berger H, Forró L and Tutiš E 2008 Nat. Mater. 7 960
[19] Chang J, Blackburn E, Holmes A T, Christensen N B, Larsen J, Mesot J, Liang R, Bonn D A, Hardy W N, Watenphul A, Zimmermann M V, Forgan E M and Hayden S M 2012 Nat. Phys. 8 871
[20] Ghiringhelli G, Le Tacon M, Minola M, Blanco-Canosa S, Mazzoli C, Brookes N B, De Luca G M, Frano A, Hawthorn D G, He F, Loew T, Sala M M, Peets D C, Salluzzo M, Schierle E, Sutarto R, Sawatzky G A, Weschke E, Keimer B and Braicovich L 2012 Science 337 821
[21] Comin R, Frano A, YeeMM, Yoshida Y, Eisaki H, Schierle E,Weschke E, Sutarto R, He F, Soumyanarayanan A, He Y, Le Tacon M, Elfimov I S, Hoffman J E, Sawatzky G A, Keimer B and Damascelli A 2014 Science 343 390
[22] Chen H, Yang H, Hu B, et al. 2021 Nature 599 222
[23] Teng X, Chen L, Ye F, et al. 2022 Nature 609 490
[24] Yin J X, Jiang Y X, Teng X, et al. 2022 Phys. Rev. Lett. 129 166401
[25] Shi X, Liu X, Li G, Zhao Z, Yang H, Lin X and Gao H J 2025 Chin. Phys. B 34 077101
[26] Dynes R C, Narayanamurti V and Garno J P 1978 Phys. Rev. Lett. 41 1509
[27] Kresse G and Hafner J 1993 Phys. Rev. B 47 558
[28] Kresse G and Furthmüller J 1996 Comput. Mater. Sci. 6 15
[29] Perdew J P, Burke K and Ernzerhof M 1996 Phys. Rev. Lett. 77 3865
[30] Grimme S, Antony J, Ehrlich S and Krieg H 2010 J. Chem. Phys. 132 154104
[31] Dion M, Rydberg H, Schröder E, Langreth D C and Lundqvist B I 2004 Phys. Rev. Lett. 92 246401
[32] Giannozzi P, Baroni S, Bonini N, et al. 2009 J. Phys.: Condens. Matter 21 395502
[33] Schlipf M and Gygi F 2015 Comput. Phys. Commun. 196 36
[34] Allen P B and Dynes R C 1975 Phys. Rev. B 12 905
[35] Zheng F, Li X B, Tan P, Lin Y, Xiong L, Chen X and Feng J 2020 Phys. Rev. B 101 100505
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