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Spatial dispersion in three-dimensional drawn magnetic metamaterials.
Alessandro Tuniz1, Benjamin Pope, Anna Wang
1Institute of Photonics and Optical Science, School of Physics, University of Sydney, NSW 2006, Australia. alessandro.tuniz@sydney.edu.au
Optics Express
|June 21, 2012
Summary
Spatial dispersion in terahertz metamaterials shifts resonant frequency with incident angle. Breaking longitudinal invariance via laser ablation eliminates this effect, aligning with simulations.
Area of Science:
- Metamaterials Science
- Terahertz Spectroscopy
- Electromagnetism
Background:
- Metamaterials exhibit unique electromagnetic properties.
- Spatial dispersion describes how wave properties depend on wavevector.
- Terahertz frequencies offer novel applications in sensing and imaging.
Purpose of the Study:
- To characterize spatial dispersion in longitudinally invariant metamaterials.
- To develop an analytical model for predicting resonant frequency shifts.
- To investigate methods for eliminating spatial dispersion.
Main Methods:
- Experimental characterization of metamaterial response at terahertz frequencies.
- Development of a simple analytical model for spatial dispersion.
- Laser ablation to break longitudinal invariance.
Main Results:
- Spatial dispersion was observed, causing resonant frequency shifts with incident angle.
- An analytical model accurately predicted the observed frequency shifts.
- Laser ablation successfully eliminated spatial dispersion.
Conclusions:
- Longitudinally invariant metamaterials exhibit significant spatial dispersion.
- Analytical modeling provides a predictive tool for metamaterial behavior.
- Breaking longitudinal invariance is an effective strategy to control spatial dispersion.
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