12:30–2:30 pm
Please Join us:
Spoorthi Nagasamudram’s PhD Thesis Defense
Thursday, February 29, at 12:30 pm CDT
OPTICAL MAGNETIC DIPOLE MIE RESONANCES AND ELECTRODYNAMIC INTERACTIONS IN HIGH-INDEX DIELECTRIC NANOPARTICLE BASED OPTICAL MATTER SYSTEMS
Light-matter interactions have been a subject of fascination for many years. One of the ways to examine the interactions of matter on the micro or nano scale with light is to use optical tweezers or optical trapping. When two or more micron- or nano-sized particles are illuminated by an optical trap, their mutual scattering of light results in active, non-equilibrium and self-organizing ordered structures known as optical matter. This phenomenon and the energy of interaction is known as optical binding. This thesis introduces novel light-matter interactions using high-index silicon nanoparticles. Due to their high index of refraction, silicon nanoparticles (Si NPs) exhibit a significant optical magnetic dipole (MD) resonance at vis/IR frequencies. The presence of the MD resonance in (sufficiently large) silicon nanoparticles has profound consequences on the optical forces experienced by the nanoparticles, including optical magnetic (dipole) binding forces. These forces have a big impact on various characteristics of optical matter systems such as non-reciprocity and the collective scattering behavior in multiparticle optical matter systems. These phenomena were previously only explored in metallic nanoparticles such as gold and silver, which do not have a significant MD resonance.
Committee Members:
Norbert Scherer (Chair)
Heinrich Jaeger
Aashish Clerk
Paolo Privitera
Spoorthi will be working as a process engineer at Intel in Hillsboro, Oregon.