Wavelength-dependent holographic impedance metasurfaces

Area of Science:

• Electromagnetics and Metamaterials
• Applied Physics
• Microwave Engineering

Background:

• Metasurfaces enable control over electromagnetic waves by manipulating surface impedance.
• Holographic principles, traditionally used in optics, can be adapted for beam shaping in microwave applications.
• Controlling multiple wavelengths with a single metasurface presents a significant challenge.

Purpose of the Study:

• To propose and demonstrate a single-layer multiplexing holographic impedance metasurface for independent beam shaping at two different wavelengths.
• To achieve independent control over radiation performance for distinct wavelengths using a novel unit cell design.
• To experimentally validate the proposed metasurface design for dual-wavelength beam manipulation.

Main Methods:

• Design of a single-layer holographic impedance metasurface incorporating a novel unit cell with two eigen-modes.
• Utilizing in-plane feeding for efficient wave manipulation.
• Fabrication and experimental testing of the designed metasurface sample.

Main Results:

• Successful demonstration of independent beam shaping at two distinct wavelengths.
• Generation of a left-hand circular polarization (LHCP) broadside beam at one wavelength and a right-hand circular polarization (RHCP) broadside beam at another wavelength.
• Good agreement between simulated and measured results, validating the design's effectiveness.

Conclusions:

• The proposed holographic impedance metasurface offers an effective method for dual-wavelength beam shaping with independent polarization control.
• The novel unit cell design allows for independent control over radiation performance at different wavelengths, even with a large wavelength ratio.
• This technology holds promise for advanced applications in microwave and antenna systems requiring multi-functional beam control.