Nanoscale Plasmonic Networks

Charles Lin

Helmy Group, Photonics

Abstract:

Plasmonic slot waveguides (PSWs) have received a lot of interest in the last few years because their ability to localize electromagnetic field at the subwavelength scale not only leads to novel physical effects, but also enables the realization of densely-integrated optoelectronic devices. The small footprint, versatile functionality, low parasitics and hence high speed and low power consumption are some of the advantages offered by PSW-based nanophotonic circuits. Despite the promise of PSWs, several design bottlenecks first need to be resolved: the lack of efficient waveguide excitation mechanism, the stringent device fabrication requirement, and the computationally intensive device simulation process. In this talk, potential solutions to address each of these challenges will be discussed.

First, I will introduce an orthogonal coupling scheme between conventional dielectric waveguides and PSWs. I will show that, by connecting the two waveguides in an orthogonal, end-fire configuration, the momentum mismatch between them can be minimized, leading to broadband, instantaneous, and highly efficient energy transfer. Next, I will present a mesh-based PSW device design approach, where intersecting PSWs are integrated into 2D network structures. By manipulating the mesh topology, it is possible to create compact, interference-based PSW devices that are easy to fabricate. Both the underlying physical mechanisms and the design freedoms of PSW mesh devices will be discussed. Finally, I will present a closed-form model that can handle arbitrary PSW mesh configurations. The model relies on impedance and Scattering matrix analysis to provide accurate and efficient means for device design, optimization, and sensitivity analysis. I will demonstrate the model's capability through the development of various filter and resonant devices.

Biography:

Charles Lin obtained his B.A.Sc. and M.A.Sc. degrees in electrical engineering at University of Toronto in 2010 and 2012 respectively. He is currently pursuing his Ph.D degree in Professor Amr Helmy's group. His research interests include the fundamental investigation of plasmonic behavior, plasmonic network devices, and fabrication techniques and models for plasmonic structures.