Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical properties and carrier dynamics in Co-doped ZnO nanorods   The controlled modification of the electronic properties of ZnO nanorods via
transition metal doping is reported. A series of ZnO nanorods were synthesized
by chemical bath growth with varying Co content from 0 to 20 atomic % in the
growth solution. Optoelectronic behavior was probed using cathodoluminescence,
time-resolved luminescence, transient absorbance spectroscopy, and the incident
photon-to-current conversion efficiency (IPCE). Analysis indicates the crucial
role of surface defects in determining the electronic behavior. Significantly,
Co-doping extends the light absorption of the nanorods into the visible region,
increases the surface defects, shortens the non-radiative lifetimes, while
leaving the radiative lifetime constant. Furthermore, for 1 atomic % Co-doping
the IPCE of the ZnO nanorods is enhanced. These results demonstrate that doping
can controllably tune the functional electronic properties of ZnO nanorods for
applications.

11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci