First-principles study of Casimir repulsion in metamaterials

Area of Science:

• Condensed matter physics
• Quantum field theory
• Nanotechnology

Background:

• The Casimir effect typically results in an attractive force between closely spaced objects.
• Controlling or reversing the Casimir force is crucial for micro/nanoscale device applications.
• Metamaterials offer unique electromagnetic properties not found in natural materials.

Purpose of the Study:

• To theoretically investigate the Casimir effect between metallic plates and magnetic metamaterials.
• To explore the possibility of achieving Casimir repulsion.
• To identify metamaterial designs capable of manipulating Casimir forces.

Main Methods:

• Utilizing a rigorous multiple-scattering theory for Casimir effect calculations.
• Examining two-dimensional lattices of nonmagnetic spheres with polariton resonances.
• Investigating lattices of superparamagnetic composite spheres.

Main Results:

• Nonmagnetic polaritonic metamaterials resulted in an attractive Casimir force.
• Magnetic metamaterials composed of superparamagnetic spheres demonstrated Casimir repulsion.
• Near-total suppression of the Casimir effect was achieved at the micrometer scale.

Conclusions:

• Magnetic metamaterials, specifically superparamagnetic composites, can be engineered to generate repulsive Casimir forces.
• The Casimir effect can be significantly suppressed or even reversed using tailored magnetic metamaterials.
• This work provides a theoretical framework for designing metamaterials to control Casimir interactions.