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Topological Fermiology of gate-tunable Rashba electron gases
Jie Hu1, Ze-Zheng Fang1, Feng Sheng1
1School of Physics and State Key Laboratory of Silicon and Advanced Semiconductor Materials, Zhejiang University, Hangzhou 310027, P. R. China.
Science Advances
|November 20, 2024
Summary
This study demonstrates topo-Fermiology in black arsenic, revealing quantum phases and Fermi surface topology. This method precisely probes topological quantum matter using magnetic quantum oscillations.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Topological Matter
Background:
- Magnetic quantum oscillations are vital for probing Fermi surface topology.
- Recent theories introduce first-order quantum phases as topological invariants.
- Topo-Fermiology combines Fermi surface topology and geometric information.
Purpose of the Study:
- To demonstrate comprehensive topo-Fermiology in high-mobility Rashba two-dimensional electron gases.
- To investigate the tunability of spin-orbit coupling in few-layer black arsenic.
- To establish topo-Fermiology as a key methodology for topological quantum matter.
Main Methods:
- Utilizing magnetic quantum oscillations in few-layer black arsenic.
- Employing gate-tunability to control spin-orbit coupling parameter.
- Analyzing Landau level crossings and quantum Hall effect phenomena.
Main Results:
- Observed period doubling in quantum oscillations, consistent with theory.
- Demonstrated gate-tunable aperiodic beating patterns.
- Showcased symmetry-enforced Landau level crossings influenced by Rashba and Zeeman interactions.
- Revealed odd-filling factor integer quantum Hall effect.
Conclusions:
- Topo-Fermiology is a powerful tool for studying topological quantum matter.
- The findings validate theoretical predictions for Rashba systems.
- This work highlights the potential of black arsenic for topological studies.
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