Universal nonresonant absorption in carbon nanotubes

Universal Density of States for Carbon Nanotubes

The density of states in the vicinity of the Fermi level of single-wall carbon nanotubes can be expressed in terms of a universal relationship that depends only on whether the nanotube is metallic or semiconducting. We compare the predictions of this approximate relationship with densities of states calculated using first-principles band structure results. These comparisons show that this appro...

Microwave Absorption Characteristics of Carbon Nanotubes

Triplet state absorption in carbon nanotubes: a TD-DFT study.

We predict properties of triplet excited states in single-walled carbon nanotubes (CNTs) using a time-dependent density-functional theory (TD-DFT). We show that the lowest triplet state energy in CNTs to be about 0.2-0.3 eV lower than the lowest singlet state energies. Like in pi-conjugated polymers, the lowest CNT triplets are spatially localized. These states show strong optical absorption at...

Absorption spectroscopy of individual single-walled carbon nanotubes.

Current methods for producing single-walled carbon nanotubes (SWNTs) lead to heterogeneous samples containing mixtures of metallic and semiconducting species with a variety of lengths and defects. Optical detection at the single nanotube level should thus offer the possibility to examine these heterogeneities provided that both SWNT species are equally well detected. Here, we used photothermal ...

Chirality dependence of the absorption cross section of carbon nanotubes.

The variation of the optical absorption of carbon nanotubes with their geometry has been a long-standing question at the heart of both metrological and applicative issues, in particular because optical spectroscopy is one of the primary tools for the assessment of the chiral species abundance of samples. Here, we tackle the chirality dependence of the optical absorption with an original method ...