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Liu C, Zhou Y, Wang G, Yin Y, Li C, Huang H, Guan D, Li Y, Wang S, Zheng H, Liu C, Han Y, Evans JW, Liu F, Jia J. Sierpiński Structure and Electronic Topology in Bi Thin Films on InSb(111)B Surfaces. PHYSICAL REVIEW LETTERS 2021; 126:176102. [PMID: 33988396 DOI: 10.1103/physrevlett.126.176102] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 02/11/2021] [Accepted: 03/19/2021] [Indexed: 06/12/2023]
Abstract
Deposition of Bi on InSb(111)B reveals a striking Sierpiński-triangle (ST)-like structure in Bi thin films. Such a fractal geometric topology is further shown to turn off the intrinsic electronic topology in a thin film. Relaxation of a huge misfit strain of about 30% to 40% between Bi adlayer and substrate is revealed to drive the ST-like island formation. A Frenkel-Kontrova model is developed to illustrate the enhanced strain relief in the ST islands offsetting the additional step energy cost. Besides a sufficiently large tensile strain, forming ST-like structures also requires larger adlayer-substrate and intra-adlayer elastic stiffnesses, and weaker intra-adlayer interatomic interactions.
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Affiliation(s)
- Chen Liu
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yinong Zhou
- Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA
| | - Guanyong Wang
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yin Yin
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Can Li
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Haili Huang
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Dandan Guan
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
- Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yaoyi Li
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
- Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Shiyong Wang
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
- Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hao Zheng
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
- Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Canhua Liu
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
- Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yong Han
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
- Ames Laboratory, U.S. Department of Energy, Ames, Iowa 50011, USA
| | - James W Evans
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
- Ames Laboratory, U.S. Department of Energy, Ames, Iowa 50011, USA
| | - Feng Liu
- Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, USA
| | - Jinfeng Jia
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
- Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China
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Tamtögl A, Sacchi M, Avidor N, Calvo-Almazán I, Townsend PSM, Bremholm M, Hofmann P, Ellis J, Allison W. Nanoscopic diffusion of water on a topological insulator. Nat Commun 2020; 11:278. [PMID: 31937778 PMCID: PMC6959239 DOI: 10.1038/s41467-019-14064-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 12/13/2019] [Indexed: 11/12/2022] Open
Abstract
The microscopic motion of water is a central question, but gaining experimental information about the interfacial dynamics of water in fields such as catalysis, biophysics and nanotribology is challenging due to its ultrafast motion, and the complex interplay of inter-molecular and molecule-surface interactions. Here we present an experimental and computational study of the nanoscale-nanosecond motion of water at the surface of a topological insulator (TI), Bi[Formula: see text]Te[Formula: see text]. Understanding the chemistry and motion of molecules on TI surfaces, while considered a key to design and manufacturing for future applications, has hitherto been hardly addressed experimentally. By combining helium spin-echo spectroscopy and density functional theory calculations, we are able to obtain a general insight into the diffusion of water on Bi[Formula: see text]Te[Formula: see text]. Instead of Brownian motion, we find an activated jump diffusion mechanism. Signatures of correlated motion suggest unusual repulsive interactions between the water molecules. From the lineshape broadening we determine the diffusion coefficient, the diffusion energy and the pre-exponential factor.
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Affiliation(s)
- Anton Tamtögl
- Institute of Experimental Physics, Graz University of Technology, 8010, Graz, Austria.
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge, CB3 0HE, UK.
| | - Marco Sacchi
- Department of Chemistry, University of Surrey, Guildford, GU2 7XH, UK
| | - Nadav Avidor
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge, CB3 0HE, UK
| | - Irene Calvo-Almazán
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge, CB3 0HE, UK
- Material Science Division, Argonne National Laboratory, Argonne, 60439, IL, USA
| | - Peter S M Townsend
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge, CB3 0HE, UK
- Department of Chemistry and Chemical Biology, Rutgers University, 123 Bevier Road, Piscataway, NJ, 08854, USA
| | - Martin Bremholm
- Center for Materials Crystallography, Department of Chemistry and iNANO, Aarhus University, 8000, Aarhus, Denmark
| | - Philip Hofmann
- Department of Physics and Astronomy, Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000, Aarhus C, Denmark
| | - John Ellis
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge, CB3 0HE, UK
| | - William Allison
- Cavendish Laboratory, J. J. Thompson Avenue, Cambridge, CB3 0HE, UK
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