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Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light
Published on: July 29, 2013
Topological Anderson insulator.
Jian Li1, Rui-Lin Chu, J K Jain
1Department of Physics and Center of Computational and Theoretical Physics, The University of Hong Kong, Pokfulam Road, Hong Kong.
Physical Review Letters
|April 28, 2009
Summary
Disorder creates a novel topological Anderson insulator phase. This phase, unlike typical insulators, features extended edge states crucial for quantum spin Hall effect applications.
Area of Science:
- Condensed matter physics
- Topological materials science
Background:
- Disorder is key to phenomena like metal-insulator transitions and quantum Hall effects.
- Topological insulators exhibit helical edge states and the quantum spin Hall effect.
Purpose of the Study:
- Investigate disorder's role in topological insulators.
- Predict and characterize a new quantum phase: the topological Anderson insulator.
Main Methods:
- Introducing impurities into a two-dimensional metal.
- Analyzing the resulting metal-insulator transition and edge state behavior.
Main Results:
- Disorder induces a metal-insulator transition.
- Disorder is essential for creating extended edge states in the topological Anderson insulator.
- The phase diagram for this new topological phase was determined.
Conclusions:
- The topological Anderson insulator represents a novel quantum phase driven by disorder.
- Disorder's role extends beyond simple transitions to actively creating topological states.
- Experimental consequences of this phase were outlined for future research.
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