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Symmetry-protected topological orders in interacting bosonic systems
Xie Chen1, Zheng-Cheng Gu, Zheng-Xin Liu
1Department of Physics, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|December 22, 2012
Summary
Researchers systematically constructed novel symmetry-protected topological (SPT) phases in interacting bosonic systems using group cohomology. This work uncovers new bosonic topological insulators and superconductors, expanding the understanding of quantum matter.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Topological Phases of Matter
Background:
- Symmetry-protected topological (SPT) phases are quantum phases with symmetries and unique boundary states.
- Existing classification of SPT phases is limited, particularly for interacting systems.
Purpose of the Study:
- To systematically construct SPT phases in interacting bosonic systems.
- To discover new types of bosonic topological insulators and superconductors.
Main Methods:
- Utilized group cohomology theory for systematic construction.
- Applied methods to interacting bosonic systems in any dimension and with any symmetry.
Main Results:
- Developed a systematic framework for constructing interacting bosonic SPT phases.
- Identified novel bosonic topological insulators and superconductors.
Conclusions:
- Group cohomology provides a powerful tool for classifying and constructing SPT phases.
- The findings expand the landscape of known topological phases in quantum matter.
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