Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Highly enhanced field emission current density of copper oxide coated
  vertically aligned carbon nanotubes: Role of interface and electronic
  structure   We report the field emission (FE) properties of Cu coated vertically aligned
carbon nanotubes (VACNTs) before and after oxidation. The current density was
found to be the maximum (20 mA/cm$^2$) for 3 nm thick Cu coated VACNTs after
oxidation. The variation in conventionally monitored parameters like work
function and field enhancement factor does not explain the experimentally
determined FE current density. A critical analysis of the electronic structure
reveals the importance of presence of Cu$_2$O at the interface of CuO and
VACNTs, which in turn controls the current density of these films. The highly
enhanced FE current density of 3 nm Cu coated VACNTs after oxidation suggests
its potential as a next generation electron source in vacuum microelectronic
devices.

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The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol