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Rashba spin-orbit driven topological phase transitions in heterogeneous armchair honeycomb nanoribbons
Hao-Ru Wu1, Jhih-Shih You1, Yiing-Rei Chen1
1Department of Physics, National Taiwan Normal University, 88, Ting-Chou Rd. Sec. 4, Taipei City, 106, Taiwan.
Summary
We found that structural geometry and Rashba spin-orbit coupling (RSOC) create topological phases in nanoribbons. These topological states are tunable and emerge at interfaces, offering new ways to engineer materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Topological phases in materials offer unique electronic properties.
- Heterogeneous nanostructures provide platforms for novel quantum phenomena.
- Rashba spin-orbit coupling (RSOC) is crucial for spintronic applications.
Purpose of the Study:
- To investigate topological phases in armchair honeycomb nanoribbons.
- To explore the role of structural geometry and RSOC in phase emergence.
- To understand the localization and tunability of interface states.
Main Methods:
- Theoretical investigation of heterogeneous armchair honeycomb nanoribbons.
- Analysis of systems with a central RSOC-active region and pristine segments.
- Study of interface states and bulk energy gap evolution with RSOC strength.
Main Results:
- Nontrivial topological phases emerge due to interplay of geometry and RSOC.
- Interface states localize at junctions between topologically distinct phases.
- RSOC induces topological phase transitions by altering the bulk energy gap.
Conclusions:
- Tunable topological states can be engineered in nanoribbons.
- Interfacial structure and spin-orbit interactions are key for control.
- Findings offer a pathway for designing novel topological materials.
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