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Characterization of a planar artificial magnetic metamaterial surface
D R Smith1, D Schurig, J J Mock
1Department of Electrical and Computer Engineering, Duke University, Box 90291, Durham, North Carolina 27708, USA. drsmith@ee.duke.edu
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 10, 2006
Summary
This study shows how to measure artificial magnetism in 2D metamaterials. Reflectance measurements at oblique angles can determine bulk magnetic permeability, but only if the metamaterial element symmetry is known.
Area of Science:
- Electromagnetism
- Materials Science
- Condensed Matter Physics
Background:
- Planar artificial magnetic metamaterials are 2D structures.
- These structures lack bulk properties like electric permittivity and magnetic permeability.
- Characterizing their electromagnetic response is challenging.
Purpose of the Study:
- To develop a method for characterizing the bulk electromagnetic response of layered metamaterials.
- To relate reflectance measurements of a single metamaterial plane to bulk properties.
- To investigate the quantitative limitations of reflectance measurements for metamaterials.
Main Methods:
- Analytical theory development.
- Oblique angle reflectance measurements.
- Numerical simulations.
- Characterization of planar split ring resonator samples.
Main Results:
- A method to determine bulk magnetic permeability from single-plane reflectance at oblique angles was established.
- Analytical theory successfully relates reflectance to bulk properties.
- Reflectance measurements can detect circulating currents (precursors to magnetism).
Conclusions:
- Reflectance measurements are valuable for characterizing artificial magnetic metamaterials.
- Quantitative results require careful specification of metamaterial element symmetry.
- The approach is applicable to layered metamaterial structures.
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