Critical coupling-assisted extraordinary electromagnetic transmission unrestricted by aperture size

Area of Science:

• Physics
• Metamaterials
• Optics

Background:

• Extraordinary electromagnetic transmission (EET) enhances light transmission through subwavelength apertures in metal films.
• Achieving ultrahigh EET through very small apertures remains a significant challenge in optics and photonics.

Purpose of the Study:

• To demonstrate near-unity extraordinary electromagnetic transmission using a wire-through-hole metasurface.
• To show that the EET effect is not constrained by the metal aperture size.

Main Methods:

• Utilized the principle of critical coupling.
• Designed and simulated a wire-through-hole metasurface.
• Conducted experimental validation of the proposed mechanism.

Main Results:

• Achieved near-unity (up to 100% in simulations, 93.7% in experiments) extraordinary transmission.
• Demonstrated that the transmission efficiency is independent of the aperture size.
• Showcased arbitrary polarization rotation of the transmitted wave without loss of efficiency.

Conclusions:

• Introduced a novel mechanism for achieving ultrahigh extraordinary electromagnetic transmission.
• Laid the foundation for developing advanced devices like high-efficiency sensors, filters, and communication systems.