Doctor of Philosophy
Rotkin, Slava V.
Other advisers/committee members
Biaggio, Ivan; Dierolf, Volkmar; Stavola, Michael; Fowler, W. Beall; Jagota, Anand
We theoretically study the near-field electromagnetic effects of a single-walled carbon nanotube (SWNT) antenna. We develop a model for plasmon resonances on the SWNT surface by treating the SWNT as a transmission line (TL). By defining TL parameters such as resistance, capacitance, and inductance per unit length of the SWNT antenna, we effectively model the plasmon resonances which have fundamental modes in the THz frequency range.We also include excitonic effects into our SWNT antenna to model the antenna response in the visible/NIR frequency range. A quasi-classical expression for the excitonic conductivity is derived. From Maxwell's equations, an integral equation for the induced current distribution due to an external field is solved. The scattered field from the excitonic antenna can be calculated from the current distribution and localized hotspots are observed. By placing rare earth ions (REIs) in the local hotspots of the SWNT antenna, we can calculate the excitation enhancements of multiple REI transitions and multiple chirality SWNT antennas. REI excitation enhancements ranging from 1-200% are calculated. Evidence of exciton-polariton modes due to the coupling of photons to the antenna resonances are also observed. These modes are allowed when the real part of the complex dielectric function is negative. The polariton modes follow a pi/L wave vector dependence.
Sofka, Benjamin, "Near-Field Electromagnetic Interactions in SWNT/REI Complexes" (2016). Theses and Dissertations. 2816.
Available for download on Friday, June 01, 2018