Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Improvement and protection of niobium surface superconductivity by
  Atomic Layer Deposition and heat treatment   A method to treat the surface of Nb is described which potentially can
improve the performance of superconducting RF cavities. We present tunneling
and x-ray photoemission spectroscopy (XPS) measurements at the surface of
cavity-grade niobium samples coated with a 3 nm alumina overlayer deposited by
Atomic Layer Deposition (ALD). The coated samples baked in ultra high vacuum
(UHV) at low temperature reveal at first degraded superconducting surface.
However, at temperatures above 450C, the tunneling conductance curves show
significant improvements of the superconducting density of states (DOS)
compared with untreated surfaces.

29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs