Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Excitons in quasi-one dimensional organics: Strong correlation
  approximation   An exciton theory for quasi-one dimensional organic materials is developed in
the framework of the Su-Schrieffer-Heeger Hamiltonian augmented by short range
extended Hubbard interactions. Within a strong electron-electron correlation
approximation, the exciton properties are extensively studied. Using scattering
theory, we analytically obtain the exciton energy and wavefunction and derive a
criterion for the existence of a $B_u$ exciton. We also systematically
investigate the effect of impurities on the coherent motion of an exciton. The
coherence is measured by a suitably defined electron-hole correlation function.
It is shown that, for impurities with an on-site potential, a crossover
behavior will occur if the impurity strength is comparable to the bandwidth of
the exciton, corresponding to exciton localization. For a charged impurity with
a spatially extended potential, in addition to localization the exciton will
dissociate into an uncorrelated electron-hole pair when the impurity is
sufficiently strong to overcome the Coulomb interaction which binds the
electron-hole pair. Interchain coupling effects are also discussed by
considering two polymer chains coupled through nearest-neighbor interchain
hopping $t_{\perp}$ and interchain Coulomb interaction $V_{\perp}$. Within the
$t$ matrix scattering formalism, for every center-of-mass momentum, we find two
poles determined only by $V_{\perp}$, which correspond to the interchain
excitons. Finally, the exciton state is used to study the charge transfer from
a polymer chain to an adjacent dopant molecule.

24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an