Date of Graduation
Doctor of Philosophy in Physics (PhD)
Joseph B. Herzog
Surendra P. Singh
Second Committee Member
2D material, Adhesion, dispersion mode hybridization process, Graphene, Hyperbolic, Maxwell equations, Phosphorene, Plasmonics, thermovoltaic
Recently, various groups have demonstrated nano-scale engineering of nanostructures for optical to infrared wavelength plasmonic applications. Most fabrication technique processes, especially those using noble metals, requires an adhesion layer. Previously proposed theoretical work to support experimental measurement often neglect the effect of the adhesion layers. The first finding of this work focuses on the impact of the adhesion layer on nanoparticle plasmonic properties. Gold nanodisks with a titanium adhesion layer are investigated by calculating the scattering, absorption, and extinction cross-section with numerical simulations using a finite difference time domain (FDTD) method. I demonstrate that a gold nanodisk with an adhesive layer significantly shifts the plasmon resonance relative to one without adhesion material. In addition, the adhesive layer also introduces stronger damping and decay time. Next, I investigate the plasmonic properties and effects of dielectric environment of black phosphorene (BP), a newly discovered anisotropic 2D material. Results suggest that the surface plasmon properties of a black phosphorene nanoribbon could be exploited to probe the efficiency of edge plasmonic enhanced absorption. Furthermore, the enhanced absorption of periodic BP nanoribbons is affected strongly by high density free carriers in BP nanoribbon geometries from mid-infrared to high infrared regime. Also when adding a thin dielectric shielding layer, such as hexagonal boron nitride, in addition to preserving the edge mode plasmonic nature of BP, it also allows for an unprecedented control of the absorption resonance energy. Finally, I also show monolayer graphene surface plasmon hybridization with hyperbolic phonon polarization local density of state of hyperbolic ferroelectric LiNbO3. The results show that the dispersion mode hybridization process is significantly regulated by a electrostatic gated single graphene and double graphene layer in addition to the ferroelectric layer size. The spontaneous emission (SE) rate the hyperbolic band contribution of LiNbO3 with graphene integrated system elucidated enhancement and inhibit spontaneous emission. Specially, the SE rate between in hybrid system is always smaller than that of the bulk in the hyperbolic band region with higher chemical potential.
Debu, Desalegn Tadesse, "Plasmonic Properties of Nanoparticle and Two Dimensional Material Integrated Structure" (2019). Theses and Dissertations. 3190.