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Extended Haldane model- a modern gateway to topological insulators
Tanay Nag1, Saptarshi Mandal2,3
1Department of Physics, BITS Pilani-Hyderabad Campus, Telangana 500078, India.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|February 17, 2025
Summary
This study explores the extended Haldane model, revealing topological insulator phases and anomalous quantum Hall effects. It also demonstrates higher-order topological insulators and discusses emergent symmetries for broader understanding.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- The Haldane model introduced topological phases beyond the quantum Hall effect.
- Honeycomb lattices are key platforms for exploring novel topological states.
Purpose of the Study:
- To investigate topological features in an extended Haldane model with spin-orbit interaction and Zeeman field.
- To elucidate first-order and higher-order topological insulator phases and their characterization.
Main Methods:
- Analysis of the extended Haldane model across its full parameter space.
- Characterization of topological phases, including anomalous quantum Hall and quantum spin Hall effects.
- Demonstration of higher-order topological insulator concepts in the anisotropic limit.
Main Results:
- Identification of various first-order topological insulator phases.
- Explanation of anomalous quantum Hall effects and quantum spin Hall effects.
- Demonstration of higher-order topological insulator phases and topological invariants.
Conclusions:
- The extended Haldane model provides a rich platform for understanding diverse topological phenomena.
- Further research into emergent symmetries can broaden the understanding of topological phase emergence criteria.
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