Work

Sub-diffractional waveguiding by mid-infrared plasmonic resonators in semiconductor nanowires

Year: 2018
Type: article
Abstract: Chains of nanoscale plasmonic resonators are capable of sub-diffractional waveguiding and have applications in nanophotonics and thermal radiation transport. Practical uses have largely been limited, however, due to high optical losses or low group velocities. Here, we predict the waveguide performance of a material structure capable of overcoming these limitations: plasmonic resonators embedded in high-dielectric nanowires. Due to the enhanced near-field coupling between resonators, we find that the group velocities and propagation lengths for doped Si plasmonic resonators in intrinsic Si nanowires can be increased by up to an order of magnitude compared to the case of isotropic vacuum surroundings. We investigate the impact of resonator aspect ratio, doping, and spacing on waveguide performance, and we find that propagation lengths are maximized for large aspect ratios and high dopant concentrations at small spacings. To study these complex anisotropic systems, we develop a new analytical "absorption spectra" method to extract waveguide information from simple far-field absorption experiments (or simulations) of only two coupled resonators.
Source: Nanoscale
Language: English
Open Access status: green
OpenAlex ID: W2793729927
FWCI: 0.593
Cites: 50
Cited by: 7
Related to: 10