Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tuning carrier density and phase transitions in oxide semiconductors
  using focused ion beams   We demonstrate spatial modification of the optical properties of thin-film
metal oxides, zinc oxide and vanadium dioxide as representatives, using a
commercial focused ion beam (FIB) system. Using a Ga+ FIB and thermal
annealing, we demonstrated variable doping of a band semiconductor, zinc oxide
(ZnO), achieving carrier concentrations from 10^18 cm-3 to 10^20 cm-3. Using
the same FIB without subsequent thermal annealing, we defect-engineered a
correlated semiconductor, vanadium dioxide (VO2), locally modifying its
insulator-to-metal transition (IMT) temperature by range of ~25 degrees C. Such
area-selective modification of metal oxides by direct writing using a FIB
provides a simple, mask-less route to the fabrication of optical structures,
especially when multiple or continuous levels of doping or defect density are
required.

18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
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The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
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The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-ex