Slow waves in locally resonant metamaterials line defect waveguides

Area of Science:

• Physics
• Materials Science
• Engineering

Background:

• Wave slowing is crucial for analog signal computing and enhancing wave/matter interactions.
• Current slow light components are typically optics-based and operate at the wavelength scale, limiting their use at lower frequencies.

Purpose of the Study:

• To overcome the frequency limitations of existing slow light technologies.
• To demonstrate a novel approach for achieving slow wave propagation at the sub-wavelength scale.

Main Methods:

• Utilized locally resonant metamaterials with coupled resonant defects.
• Engineered sub-wavelength waveguides within these metamaterials.
• Experimentally investigated wave propagation in the microwave regime.

Main Results:

• Achieved reduced group velocities in sub-wavelength waveguides.
• Demonstrated tunable wave velocity with group indices as high as 227.
• Observed extreme field confinement for enhanced wave/matter interactions.

Conclusions:

• Developed a compact platform for low-frequency slow light using sub-wavelength metamaterials.
• The approach enables efficient wave/matter interactions due to high group indices and field confinement.
• Slow wave propagation was achieved without significant bandwidth reduction, offering a significant advantage over other methods.