Evidence for Two-Dimensional Weyl Fermions in Air-Stable Monolayer PtTe1.75
Zhihao Cai1,2, Haijun Cao1,2, Haohao Sheng1,2
1Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Nano Letters
|August 2, 2024
Summary
Researchers discovered two-dimensional (2D) Weyl Fermions in monolayer platinum telluride (PtTe1.75). This breakthrough in topological materials paves the way for advanced spintronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Physics
Background:
- Weyl semimetals exhibit unique topological properties due to Weyl Fermions.
- Realizing two-dimensional (2D) Weyl semimetals remains a significant challenge in materials science.
- These materials are predicted to have exotic transport and optical properties.
Purpose of the Study:
- To experimentally realize and characterize 2D Weyl Fermions.
- To investigate the potential of monolayer PtTe1.75 as a platform for 2D Weyl Fermions.
- To explore the implications for future spintronic device applications.
Main Methods:
- Combined experimental techniques: angle-resolved photoemission spectroscopy, scanning tunneling microscopy, second harmonic generation, and X-ray photoelectron spectroscopy.
- First-principles calculations to support experimental findings.
- Characterization of monolayer PtTe1.75's electronic structure and properties.
Main Results:
- Successful realization of 2D Weyl Fermions in monolayer PtTe1.75.
- Observation of strong spin-orbit coupling and lack of inversion symmetry in the material.
- Identification of three pairs of critical Weyl cones arising from giant Rashba splitting and band inversion.
- Demonstration of excellent chemical stability of monolayer PtTe1.75 under ambient conditions.
Conclusions:
- Monolayer PtTe1.75 serves as a viable platform for realizing 2D Weyl Fermions.
- The discovery opens new avenues for the design and fabrication of novel spintronic devices.
- The material's stability is advantageous for practical device applications.
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