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Updated: Jun 14, 2026
09:19
Fabrication and Characterization of Disordered Polymer Optical Fibers for Transverse Anderson Localization of Light
Published on: July 29, 2013
Dispersive cylindrical cloaks under nonmonochromatic illumination
Christos Argyropoulos1, Efthymios Kallos, Yang Hao
1Department of Electronic Engineering, Queen Mary, University of London, London, United Kingdom. christos.a@elec.qmul.ac.uk
Summary
Researchers studied transformation-based cloaking devices using nonmonochromatic waves, observing unusual transient effects. These findings are crucial for designing effective metamaterial devices, considering factors like bandwidth and wave disturbances.
Area of Science:
- Metamaterials
- Electromagnetism
- Wave Phenomena
Background:
- Transformation-based cloaks and concentrators are advanced optical devices.
- Their performance with nonmonochromatic waves is not fully understood.
- Metamaterial devices often exhibit dispersive properties.
Purpose of the Study:
- To investigate the transient responses of cylindrical cloaks and concentrators under nonmonochromatic illumination.
- To analyze the effects of bandwidth, losses, and inherent dispersion on device performance.
- To identify and characterize unusual wave phenomena and their implications.
Main Methods:
- Numerical simulations using the finite-difference time-domain (FDTD) method.
- Verification of numerical results with analytical formulas.
- Computation of effective bandwidth and analysis of loss effects.
Main Results:
- Observed unusual transient effects and phenomena with nonmonochromatic waves.
- Identified narrowband behavior, frequency shifts, time delays, and spatial wave disturbances.
- Quantified the impact of losses on cloaking and concentrating performance.
Conclusions:
- The inherent dispersion of transformation-based devices significantly influences their performance with broadband waves.
- Frequency shifts, time delays, and spatial disturbances are dominant effects that must be considered.
- These findings are critical for the practical design and application of metamaterial-based cloaking and concentrating devices.
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