I work in the MBE Lab, which is part of the Materials Department and manufactures inorganic semiconductor materials through the process of molecular beam epitaxy. So what is MBE?

It is the method that creates materials of the highest achievable purity in grown films and involves the use of a large machine with ultra high vacuum contained compartments. Elements are heated in separate cells until they begin to sublime, at which point they condense on a wafer and interact with each other to create a thin film. It is called “beam” because ideally the atoms of the elements do not interact until they settle on the wafer. The term “epitaxy” means that the molecules are deposited in a crystalline form in layers over the substrate.

My main research project is concerned with plasmonics, the practice of using nanostructures to manipulate light through a composite material. I work with a material composed of a semiconductor matrix embedded with semimetallic nanoparticles that is grown by MBE. When light waves hit the nanoparticles, the electric field of the wave causes the free electrons of the nanoparticles to move away from the positive nucleus. The restoring force then pulls the electrons back toward the nucleus. This motion continues, and the electrons oscillate back and forth. Surface plasmon resonance occurs when the light frequency matches the oscillation frequency.

I am working to extrapolate the properties of this material using the observed absorption data. We hope to construct a curve based on the surface plasmon resonance theory that fits the experimental data. Through this process, we can discern features of the matrix material such as the dielectric function and the carrier concentration, which need to be considered when the material is used in other applications.