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Quantum spin Hall effect in a transition metal oxide Na2IrO3
Atsuo Shitade1, Hosho Katsura, Jan Kunes
1Department of Applied Physics, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan. shitade@appi.t.u-tokyo.ac.jp
Physical Review Letters
|August 8, 2009
Summary
We theoretically investigated electronic states in sodium iridate (Na2IrO3), revealing it as a layered quantum spin Hall system. Electron correlation drives antiferromagnetic order at the edges and then the bulk at low temperatures.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Chemistry
Background:
- Sodium iridate (Na2IrO3) is a 5d transition metal oxide.
- Both spin-orbit interaction and electron correlation are critical factors in its electronic properties.
Purpose of the Study:
- To theoretically investigate the electronic states of Na2IrO3.
- To determine the material's classification within quantum Hall systems.
- To understand the influence of electron correlation on magnetic ordering.
Main Methods:
- Tight-binding model analysis.
- First-principles band structure calculations.
Main Results:
- The study predicts Na2IrO3 is a layered quantum spin Hall system.
- Electron correlation leads to the development of antiferromagnetic order.
- Antiferromagnetic order initiates at the material's edge before appearing in the bulk at low temperatures.
Conclusions:
- Na2IrO3 exhibits unique electronic and magnetic properties driven by spin-orbit coupling and electron correlation.
- The material's behavior as a quantum spin Hall system with edge-initiated magnetic order offers potential for novel electronic applications.
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