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Hyperbolic Weyl Point in Reciprocal Chiral Metamaterials
Meng Xiao1, Qian Lin2, Shanhui Fan1
1Department of Electrical Engineering, and Ginzton Laboratory, Stanford University, Stanford, California 94305, USA.
Physical Review Letters
|August 13, 2016
Summary
Researchers found Weyl points in noncentral symmetric metamaterials with time reversal symmetry. The metamaterial exhibits type-I or type-II Weyl points based on nonlocal response, with elliptical helices realizing type-II points.
Area of Science:
- Condensed matter physics
- Electromagnetism
- Materials science
Background:
- Weyl points are exotic topological phenomena in materials.
- Noncentral symmetric metamaterials offer unique electromagnetic properties.
- Chiral coupling between electric and magnetic fields is crucial for certain topological states.
Purpose of the Study:
- To investigate the existence and types of Weyl points in noncentral symmetric metamaterials.
- To explore the role of chiral coupling in forming Weyl points.
- To propose a physical realization of metamaterials exhibiting specific Weyl point types.
Main Methods:
- Theoretical analysis of noncentral symmetric metamaterials with time reversal symmetry.
- Investigation of the influence of nonlocal response on Weyl point characteristics.
- Design and conceptualization of a metamaterial structure using elliptical helices.
Main Results:
- Demonstrated the existence of Weyl points in the studied metamaterial class.
- Showed that the type of Weyl points (Type-I or Type-II) depends on the nonlocal response.
- Proposed a physical realization of elliptical helix metamaterials exhibiting Type-II Weyl points.
Conclusions:
- Noncentral symmetric metamaterials with time reversal symmetry can host Weyl points.
- Tailoring the nonlocal response allows control over Weyl point types.
- Elliptical helix metamaterials provide a viable platform for realizing Type-II Weyl points.
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