Exciton-Plasmon Coupling in Carbon Nanotubes

TL;DR

This paper theoretically investigates the strong coupling between excitons and surface plasmons in small-diameter semiconducting carbon nanotubes, revealing significant Rabi splitting and potential for novel optoelectronic applications.

Contribution

It demonstrates the possibility of strong exciton-plasmon coupling in carbon nanotubes and characterizes the resulting spectral line splitting, advancing understanding of nanotube optoelectronics.

Findings

Observation of Rabi splitting of 0.1-0.3 eV in absorption spectra.

Identification of exciton-surface plasmon resonance conditions.

Potential for new optoelectronic device functionalities.

Abstract

We study theoretically the interactions of excitonic states with surface electromagnetic modes of small-diameter (~1 nm) semiconducting single-walled carbon nanotubes. We show that these interactions can result in strong exciton-surface-plasmon coupling. The exciton absorption lineshapes exhibit the line (Rabi) splitting $~0.1-0.3$ eV as the exciton energy is tuned to the nearest interband surface plasmon resonance of the nanotube. We expect this effect to open a path to new optoelectronic device applications of semiconducting carbon nanotubes.