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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Intrinsic coupling between spatially-separated surface Fermi-arcs in Weyl orbit quantum Hall states
Shinichi Nishihaya1, Masaki Uchida2,3,4, Yusuke Nakazawa1
1Department of Applied Physics and Quantum-Phase Electronics Center (QPEC), University of Tokyo, Tokyo, Japan.
Nature Communications
|May 7, 2021
Summary
Researchers demonstrated intrinsic coupling between spatially-separated surface states in Weyl orbits using a dual-gate Dirac semimetal film. This finding reveals the unique spatial distribution of Weyl orbits, enabling new control over quantized transport.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Phenomena
Background:
- Topological semimetals feature Weyl points and Fermi-arc states.
- Weyl orbits are proposed to link surface states across topological semimetals.
- Experimental evidence for Weyl orbit spatial distribution and quantized surface transport has been limited.
Purpose of the Study:
- To experimentally demonstrate the intrinsic coupling between spatially-separated surface states within Weyl orbits.
- To investigate the spatial distribution of quantized surface transport in Weyl orbits.
- To explore new methods for controlling quantized transport in topological semimetals.
Main Methods:
- Fabrication and measurement of a dual-gate Dirac semimetal thin film device.
- Independent control and scanning of top- and back-gate voltages.
- Observation and analysis of quantum Hall states and their modulation.
Main Results:
- Demonstrated intrinsic coupling between two spatially-separated surface states in Weyl orbits.
- Observed concomitant modulation of doubly-degenerate quantum Hall states via dual-gate control.
- Showcased a transport behavior distinct from conventional surface orbits in topological insulators.
Conclusions:
- The study provides direct experimental evidence for the unique spatial distribution of Weyl orbits.
- The findings open avenues for controlling quantized transport through external fields and interface engineering.
- This work advances the understanding and potential applications of topological semimetals.
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