Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Excitons in single-walled carbon nanotubes: environmental effect   The properties of excitons in semiconducting single-walled carbon nanotubes
(SWCNTs), isolated in vacuum or a medium, and their contributions to the
optical spectra of nanotubes are studied within the elementary potential model,
in which an exciton is represented as a bound state of two oppositely charged
quasi-particles confined to the nanotube surface. The emphasis is given on the
influence of dielectric environment surrounding a nanotube on the exciton
spectra. For nanotubes in environment with permittivity less than 1.8 the
ground-state exciton binding energies exceed the respective energy gaps, while
the obtained binding energies of excitons in nanotubes in a medium with
permittivity greater than 4 are in good accordance with the corresponding
experimental data and consistent with known scaling relation for the
environmental effect. The stabilization process of single-electron spectrum in
SWCNTs in media with rather low permittivities is discussed.

31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg