Carbon Nanotube Photoluminescence

Carbon is an amazing element, capable of forming many types of chemical bonds with other carbon atoms, leading to a wide variety of existing carbon forms. Single-walled carbon nanotubes (SWNTs) are a particularly interesting form of carbon, thanks to their low dimensionality and model structure, which give them original physical properties. Depending on their structure, SWNTs can be metallic or semiconducting. With regard to their optical properties, semiconducting SWNTs emit light in the near infrared, a phenomenon known as photoluminescence. The emission wavelengths of SWNTs are highly dependent on their structure, as well as their dielectric environment.

In this article, we discuss the physical phenomena behind the photoluminescence of semiconductor nanotubes. In particular, we describe the excitonic nature of the photoluminescence mechanism, and the strong influence of environment and structure on photoluminescence spectra. The photoluminescence properties of nanotubes are very rich, and can be put to use in a wide range of applications such as metrology, materials characterization and biological imaging. We will examine in detail the photoluminescence applications of carbon nanotubes in the field of photonics, whether for quantum information, or the realization of active optical components such as light sources or detectors.