Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electroabsorption study of index-defined semiconducting carbon nanotubes   Electroabsorption spectroscopy of well-identified index-defined
semiconducting carbon nanotubes is reported. The measurement of high definition
electroabsorption spectra allows direct indexation with unique nanotube
chirality. Results show that at least for a limited range of diameters,
electroabsorption is directly proportional to the exciton binding energy of
nanotubes. Electroabsorption is a powerful technique which directly probes into
carbon nanotube excitonic states, and may become a useful tool for in situ
study of excitons in future nanotube-based photonic devices such as
electroabsorption modulators.

10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph