Topological Optical Waveguiding in Silicon and the Transition between Topological and Trivial Defect States
Andrea Blanco-Redondo1, Imanol Andonegui1,2, Matthew J Collins3
1Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), Institute of Photonics and Optical Science (IPOS), School of Physics, The University of Sydney, New South Wales 2006, Australia.
Physical Review Letters
|May 7, 2016
Summary
Researchers demonstrated topological defect modes in silicon, enabling independent probing of topological and trivial states. This advances topologically protected waveguiding in semiconductor platforms.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Topological Physics
Background:
- One-dimensional models with topological band structures offer a simplified platform for exploring novel topological concepts.
- Topological states are robust against local perturbations, making them attractive for robust information processing.
Purpose of the Study:
- To experimentally investigate topologically protected states in silicon.
- To demonstrate independent probing of coexisting topological and trivial defect modes.
- To explore the transition between topological and trivial defect states by tuning interface configurations.
Main Methods:
- Utilized silicon as a complementary metal-oxide-semiconductor (CMOS) compatible platform.
- Studied interface states between two dimer chains with distinct Zak phases.
- Manipulated interface configurations to observe defect state transitions.
Main Results:
- Observed topologically protected states at the silicon interface.
- Demonstrated independent probing of coexisting topological and trivial defect modes.
- Showcased the transition from a single topological defect to a compound trivial defect state.
Conclusions:
- The study presents a new paradigm for topologically protected waveguiding in silicon.
- Highlights the novel concept of isolating topological and trivial defect modes within the same system.
- Suggests potential implications for advancing topological physics and robust device design.
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