Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thulium and ytterbium-doped titania thin films deposited by MOCVD   In this study we synthesized thin films of titanium oxide doped with thulium
and/or ytterbium to modify the incident spectrum on the solar cells. This could
be achieved either by photoluminescence up-converting devices, or
down-converting devices. As down-converter thin films our work deals with
thulium and ytterbium-doped titanium dioxide. Thulium and ytterbium will act as
sensitizer and emitter, respectively. The rare-earth doped thin films are
deposited by aerosol-assisted MOCVD using organo-metallic precursors such as
titanium dioxide acetylacetonate, thulium and ytterbium
tetramethylheptanedionate solved in different solvents. These films have been
deposited on silicon substrates under different deposition conditions
(temperature and dopant concentrations for example). Adherent films have been
obtained for deposition temperatures ranging from 300{\deg}C to 600{\deg}C. The
deposition rate varies from 0.1 to 1 \mu m/h. The anatase phase is obtained at
substrate temperature above 400{\deg}C. Further annealing is required to
exhibit luminescence and eliminate organic remnants of the precursors. The
physicochemical and luminescent properties of the deposited films were analyzed
versus the different deposition parameters and annealing conditions. We showed
that absorbed light in the near-UV blue range is re-emitted by the ytterbium at
980 nm and by a thulium band around 800 nm.

14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
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The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th