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Updated: May 31, 2026
10:36
Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Topological hall response from canted antiferromagnetic order ind-electron kagome systems
Waquar Ahmed1, Steffen Schäfer1, Pierre Lombardo1
1IM2NP, UMR CNRS 7334, Aix-Marseille Université, 13013 Marseille, France.
Summary
A novel quantum anomalous Hall effect emerges in kagome monolayers due to intrinsic Berry curvature from spin order, enabling integer Hall conductivities without external magnetic fields or spin-orbit coupling.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Phenomena
Background:
- The quantum anomalous Hall effect (QAHE) typically requires external magnetic fields or strong spin-orbit coupling.
- Topological phenomena in multi-orbital d-electron systems remain an active area of research.
Purpose of the Study:
- To investigate the emergence of QAHE in two-dimensional kagome monolayers.
- To explore the role of non-collinear spin order and intrinsic Berry curvature in achieving QAHE.
- To identify candidate materials and understand their topological properties.
Main Methods:
- Theoretical analysis of Berry curvature in d-electron systems with antiferromagnetic exchange.
- Investigation of scalar spin chirality and its relation to Hall conductivity.
- Exploration of topological phase transitions driven by spin order manipulation.
Main Results:
- Nontrivial intrinsic Berry curvature arises from non-collinear spin order in kagome monolayers.
- QAHE is achieved without external magnetic fields, spin-orbit coupling, or relativistic effects.
- Finite scalar spin chirality leads to integer Hall conductivities (e^2/h).
- A maximal Chern number of C = ±5 is possible in canted spin configurations.
- Topological phase transitions between opposite Chern numbers are achievable by flipping spin components.
Conclusions:
- Kagome monolayers with specific spin orders offer a platform for intrinsic QAHE.
- The findings suggest potential applications in quantum information technologies.
- Material anisotropy influences the magnitude of the QAHE, with possibilities for tuning topological properties.
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