Nanotechnology and chiroptical spectroscopy to characterise optically active chiral metamaterials

Abdulrahman, Nadia Abdulkarim (2014) Nanotechnology and chiroptical spectroscopy to characterise optically active chiral metamaterials. PhD thesis, University of Glasgow.

Abstract

Work in this thesis involves manipulating the interaction between light and matter in order to retrieve important information from adsorbed molecules, such as their structure and/or function, and henceforth, to gain insight into highly sensitive detection capabilities for biosensor applications. Such manipulation might be achieved via rationalising the surfaces of optically active metamaterials by taking full advantage of the recent growth in a variety of nanotechnology disciplines. As such, the possibility of characterising biomolecules adsorbed on the surface of chiral and achiral plasmonic metamaterials, referred to as chiral and achiral plasmonic nanostructures, have been investigated. Also, illustration and applications for the so called `Superchiral Field`, which has been generated via circular polarised light (CPL), are presented. Microscopic origin of the chiroptical second harmonic generation (SHG) signal that originates from the surface of the chiral nanostructures has been investigated. Practical visualisation via femtosecond laser beam of regions of intense plasmonic activity, i.e., hot-spot mapping, has been performed. In general, the work described in this thesis involved the use of several linear and non-linear chiroptical techniques namely as extinction (absorption and scattering), CD, ORD and SHG spectroscopy, in addition to scanning imaging namely SEM and AFM microscopy. Given that most biomolecules contain either chiral molecules or adopt chiral structures, the plasmonic nanostructures presented in this work could be used to study a wide range of biological problems, from the structure of biomolecules associated with neurodegenerative illnesses such as Alzheimer’s disease and Parkinson’s disease, to DNA and viruses. As a regard, general classifications for aspects of chirality are presented in order to emphasise the association of the samples used in this chapter with some of these aspects. All samples are fabricated via Electron Beam Lithography (EBL) in JWNC cleanroom/UK; the associated fabrication techniques, the instruments and the experimental methods are described.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Subjects: Q Science > QD Chemistry
• Colleges/Schools: College of Science and Engineering > School of Chemistry
• Supervisor's Name: Kadodwala, Dr. Malcolm and Cooke, Dr. Graeme
• Date of Award: 2014
• Depositing User: Mrs Marie Cairney
• Unique ID: glathesis:2014-5480
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 08 Sep 2014 10:51
• Last Modified: 08 Sep 2014 11:52
• URI: https://theses.gla.ac.uk/id/eprint/5480