Date of Graduation

12-2018

Document Type

Dissertation

Degree Name

Doctor of Philosophy in Physics (PhD)

Degree Level

Graduate

Department

Physics

Advisor

Joseph B. Herzog

Committee Member

William G. Harter

Second Committee Member

Hugh Churchill

Keywords

CdSe Quantum Dots, Photobrightening, Photoluminescence, Plasmonics, Quantum Dots

Abstract

Quantum dots are gaining recognition not just in the physics and chemistry community, but in the public eye as well. Quantum dot technologies are now being used in sensors, detectors, and even television displays. By exciting quantum dots with light or electricity, they can be made to emit light, and by altering the quantum dot characteristics the wavelength can be finely tuned. The light emitted can be also be made more intense by an increase in the excitation energy. The excitation light can be increased via plasmonic enhancement, leading to increased luminescence. Aside from the relatively steady-state response, quantum dots also have several time-dependent behaviors – blueing, blinking, brightening, and bleaching. Brightening has several factors which affect it and is the focus of this work. This dissertation explores one of the factors which contributes to the photobrightening, namely the intensity of the excitation light, and examines the possibility of enhancing the emitted light via a range of plasmonic geometries. Gold nanoparticles come in many shapes and sizes and are ideally suited for enhancing light in the visible wavelength. By combining gold nanoparticles with cadmium selenide quantum dots, it is possible to enhance the photobrightening effect, potentially leading to better, more effective quantum dot technologies.

Share

COinS