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Updated: Jun 24, 2025
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
8.4K
Designing edge states from fractional polarization insulators
Wei Jie Chan1, Pei-Hao Fu1, L K Ang1
1Science, Mathematics and Technology (SMT), Singapore University of Technology and Design (SUTD), 8 Somapah Road, Singapore 487372, Singapore.
Summary
We explored topological edge states in anisotropic honeycomb lattices. Disrupting symmetry in fractional polarization insulators engineers these states, enabling new device applications.
Area of Science:
- Condensed Matter Physics
- Topological Materials Science
Background:
- Anisotropic honeycomb lattices lack chiral symmetry.
- Fractional polarization (FP) insulators possess robust topological edge states (TES).
Purpose of the Study:
- Investigate theoretically disconnected dispersive edge states.
- Explore engineering of TES by symmetry disruption.
- Analyze finite-size effects on edge state configurations.
Main Methods:
- Theoretical investigation of lattice models.
- Analysis of symmetry-breaking terms.
- Examination of finite-size effects.
Main Results:
- Engineered dispersive edge states by breaking mirror or chiral symmetry.
- Achieved disconnected helical-like and chiral-like edge states via finite-size effects.
- Demonstrated manipulation of edge states in FP insulators.
Conclusions:
- Symmetry disruption and finite-size effects offer pathways to engineer topological edge states.
- Potential for novel devices utilizing topological domain walls.
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