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Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Quantum adiabatic transport in a quantum anomalous Hall insulator
Kajetan M Fijalkowski1,2, Martin Klement3,4, Nan Liu3,4
1Faculty for Physics and Astronomy (EP3), Universität Würzburg, Würzburg, Germany. kajetan.fijalkowski@uni-wuerzburg.de.
Nature Communications
|July 21, 2026
Summary
Quantum anomalous Hall edge modes exhibit robust, dissipationless quantum adiabatic transport, even at high bias voltages. This finding matches the robustness of conventional quantum Hall effects, advancing quantum metrology applications.
Area of Science:
- Condensed Matter Physics
- Quantum Materials Science
Background:
- The quantum Hall effect (QHE) demonstrates robust, dissipationless edge transport.
- Quantum anomalous Hall (QAH) edge modes in magnetic topological insulators previously showed breakdown under electrical bias due to material limitations.
- This limited their application in sensitive measurements.
Purpose of the Study:
- To investigate the nature of edge transport in QAH insulators under large electrical bias.
- To mitigate electric field effects and enable study of QAH edge modes.
- To determine if QAH edge transport exhibits quantum adiabatic properties comparable to QHE.
Main Methods:
- Utilized electrochemical potential balancing to mitigate electric field effects.
- Applied large electrical bias voltages up to 600 mV at 4.2 K.
- Studied edge transport characteristics in magnetic topological insulators.
Main Results:
- Observed ubiquitous dissipationless quantum adiabatic transport along the QAH insulator edge.
- Verified adiabaticity holds at bias voltages significantly exceeding characteristic energy scales of the QAH state.
- Demonstrated robustness comparable to conventional QHE modes.
Conclusions:
- QAH edge transport is inherently of a dissipationless quantum adiabatic nature.
- Electrochemical potential balancing effectively enables study of QAH edge transport at large biases.
- QAH edge modes show potential for high-sensitivity metrology, on par with QHE systems.
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