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Updated: Aug 5, 2026
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Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Van Hove singularity-driven Hall plateau transitions in Dirac semimetals
Jian Li1,2,3,4, Kai-He Ding1,3,4, Lijun Tang1,3,4
1School of Physics and Electronic Science, Changsha University of Science and Technology, Changsha 410076, People's Republic of China.
Summary
A van Hove singularity (VHS) splits Landau levels (LLs) in Dirac semimetals, causing irregular quantum Hall plateau transitions. This finding explains observed non-uniform Hall conductivity in experiments.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- The quantum Hall effect (QHE) in Dirac semimetals is sensitive to band structure details.
- Van Hove singularities (VHS) can significantly alter electronic properties.
Purpose of the Study:
- To investigate the influence of VHS on QHE in Dirac semimetals.
- To explain the origin of irregular Hall plateau structures.
Main Methods:
- Analytical calculations using the WKB approximation.
- Numerical simulations of Landau level (LL) spectra.
- Analysis of band structure modifications due to Dirac-cone tilting and spin-orbit coupling.
Main Results:
- A VHS induces Landau level splitting, shifting energies with decreasing VHS energy.
- LL splitting originates from LL crossing of an effective potential barrier.
- Irregular Hall plateau structures arise from LL splitting and finite-size confinement effects.
- Dirac-cone tilting and spin-orbit coupling lead to hole-pocket states and nonmonotonic Hall conductivity.
Conclusions:
- The study provides a theoretical framework for understanding VHS-induced QHE phenomena in Dirac semimetals.
- The findings offer a potential explanation for experimentally observed irregular Hall plateau evolution.
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