(170c) Engineering a Colloidal Metamaterial Comprising of Metamaterial-Capped Janus Particles for Light Harvesting Applications in Cancer Detection and Therapeutics

A material’s response to electromagnetic waves is characterized by its electric permittivity and magnetic permeability Metamaterials are non-naturally occurring materials with negative electric permittivity (ε) and/or negative magnetic permeability (μ), which endow the materials with interesting optical properties as they can be engineered to reverse the Doppler and Vavilov–Cerenkov effects or modify transmission of light through the material. Therefore, these metamaterials can be found in applications such as perfect lenses, cloaking materials, and emission enhancing coatings among others.

A newly developing field within metamaterials is metafluidic metamaterials, which couples the properties of metamaterials and fluids. Our research aims to design a new type of metafludic metamaterial, a colloidal metamaterial comprising metamaterial-capped Janus particles. Spherical particles with a metamaterial cap on one side form hyperbolic metamaterial-capped Janus particles. These particles, when dispersed in a fluid, produce the desired colloidal metamaterial. Utilizing the Janus nature of the particle, one half of the particle can be used to impart colloidal properties such as self-assembly, mobility, and dispersibility while the other half can be used to optimize the desired metamaterial effects.

The hyperbolic metamaterial used in our research is fabricated by layering alumina, germanium, and silver. The alternating layers of metals and dielectrics produce a negative electric permittivity tensor that forms the basis of the hyperbolic metamaterial. Such materials have been shown to enhance emissions when fabricated on a flat surface. However, the particle surface used to make the novel colloidal metamaterial is curved and is smaller in scale. The particles have diameters in the 1–4 μm (micron) range. We will report on optical properties and effects of the colloidal metamaterial in comparison with the same metamaterial on a flat surface.