Ultralow loss visible light metamaterials assembled by metaclusters

Area of Science:

• Photonics and Materials Science
• Optics and Electromagnetism

Background:

• Controlling light with optical metamaterials is crucial.
• Fabricating low-loss, isotropic, three-dimensional negative index metamaterials (NIMs) for visible light remains a significant challenge due to energy dissipation and meta-atom complexity.

Purpose of the Study:

• To report ultralow loss isotropic metamaterials for visible light.
• To demonstrate the inverse Doppler effect in these novel metamaterials.
• To overcome the limitations of traditional optical metamaterial fabrication.

Main Methods:

• Proposed ball-thorn-shaped metaclusters with symmetrical dielectric and discrete, surface-dispersed, super-thin silver layers (2-3 atomic layers).
• Developed a unique technique for preparing ultralow loss isotropic clusters and large 3D block samples.
• Utilized the photoreduction method to create discrete super-thin silver layers, minimizing energy loss.

Main Results:

• Achieved ultralow loss isotropic metamaterials for visible light.
• Successfully measured the negative refractive index and inverse Doppler effect for green and red light using the prism method for the first time.
• Demonstrated that discrete super-thin silver layers significantly reduce energy loss compared to traditional noble metal metamaterials.

Conclusions:

• The developed metaclusters and fabrication technique overcome the bottleneck in nano-assembled visible light metamaterials.
• This work enables the disorder assembling of ultralow loss isotropic three-dimensional large block NIMs devices of arbitrary shapes.
• Paves the way for advanced optical devices and applications utilizing negative refractive index properties in the visible spectrum.