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Topic

Novel Methods for Optical Trapping and Raman Spectroscopy of Nanoparticles

Department of Electrical and Computer Engineering

Date & location

• Monday, January 13, 2025

• 11:30 A.M.

• Engineering Office Wing

• Room 430

Reviewers

Supervisory Committee

• Dr. Reuven Gordon, Department of Electrical and Computer Engineering, University of Victoria (Supervisor)

• Dr. Levi Smith, Department of Electrical and Computer Engineering, Uvic (Member)

• Dr. Peter Loock, Department of Chemistry, UVic (Outside Member) 

External Examiner

• Dr. Francois Lagugne-Labarthet, Department of Chemistry, University of Western Ontario 

Chair of Oral Examination

• Dr. Michelle Wiebe, Department of Curriculum and Instruction, UVic

   

Abstract

This dissertation explores advanced novel techniques in optical trapping and Ra man spectroscopy, focusing on the utilization of double-nanohole (DNH) apertures. We investigate polarization selective reflection mode optical trapping, which enhances the precision and efficiency of nanoparticle manipulation. These studies investigated Raman spectroscopy with DNH trapping, demonstrating significant Raman signal enhancement due to the intense electric fields generated within the DNH gaps. This enhancement is quantified through Raman signal enhancement by using DNHs and providing insights into the mechanisms driving this phenomenon.

Additionally, we present methodologies for observing trapping in real-time using the camera in optical tweezer systems, enabling direct visualization and analysis of the trapping event.

Complementary to the experimental work, DNH simulations are conducted to model the optical and plasmonic properties of the DNH structures. These simulations offered a theoretical framework that supports and explains the experimental findings. The integration of these techniques not only advances the field of optical trap ping and Raman spectroscopy but also creates new opportunities for applications in nanotechnology and materials science.