Nanometallic structures efficiently convert light to surface plasmon-polaritons (SPPs) localized to ultra-small volumes. Such structures can provide highly enhanced fields and are of interest in applications involving plasmon-enhanced nonlinear optics. In this study, the devices consist of rectangular gold nanoantennas on a graphene layer on a SiO2/Si substrate. The nanoantennas are used to exploit SPPs to enhance the interaction between graphene and light.
Specifically, plasmon-enhanced Raman scattering from graphene is of interest. Here, the nanoantennas are spectrally-aligned with a Stokes wavelength of graphene. With the addition of a second laser source, stimulated Raman scattering can be achieved. The first laser source pumps the sample’s atoms and molecules into virtual excited states and the second one stimulates emission of a photon and relaxation to a higher mode of the ground state. This work involves designing and constructing a stimulated and spontaneous Raman microscope and also a reflectance measurement tool. Within the framework of this thesis, Raman scattering enhancement in graphene based on plasmonic resonant enhancement of the Stokes emission is demonstrated, providing a maximum cross-sectional gain of approximately 500 per antenna. This work also shows the normalized reflectance response of the nanoantenna structures of different length and width and how their resonant wavelengths shift.
Identifer | oai:union.ndltd.org:uottawa.ca/oai:ruor.uottawa.ca:10393/38127 |
Date | 17 September 2018 |
Creators | Alshehab, Maryam Habeeb |
Contributors | Berini, Pierre |
Publisher | Université d'Ottawa / University of Ottawa |
Source Sets | Université d’Ottawa |
Language | English |
Detected Language | English |
Type | Thesis |
Format | application/pdf |
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