One-dimensional Plasmons and Hybridized Coupled Polaritons in Carbon Nanotubes

TL;DR

This study uses ab-initio TDDFT simulations to analyze 1-D plasmons and polaritons in armchair carbon nanotubes, revealing unique coupling behaviors and potential nanophotonic applications.

Contribution

It provides a detailed ab-initio analysis of 1-D plasmon and polariton behaviors in CNTs, including their coupling and nonlinear effects, advancing understanding of nanophotonic phenomena.

Findings

Confirmation of T-L plasmon velocities consistent with theory and experiments.

Identification of strong harmonic generation due to nonlinearities.

Discovery of energy gaps distinct from 2-D polaritons.

Abstract

This paper presents real-time time-dependent density functional theory (TDDFT) ab-initio simulations of selected armchair carbon nanotubes (CNTs). By scaling the lengths of CNTs, we provide a comprehensive analysis of the Tomonaga-Luttinger (T-L) 1-D plasmon velocities, confirming consistency with theoretical predictions and experimental observations. Our findings include detailed visual representations of excitation densities at various resonances. Furthermore, we explore the coupling between T-L plasmons and single electron excitations, identifying distinct 1-D polariton behaviors, such as strong harmonic generation due to nonlinearities, as well as energy gaps that differ from conventional 2-D polaritons. The study highlights the unique properties of armchair SWCNTs as low-loss nanocavity resonators, demonstrating potential applications in strong light-matter coupling and other nanophotonic devices. The simulation framework employed here opens avenues for further research into 1-D plasmonic phenomena and electronic spectroscopy in complex nanostructures.