Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The effects of oxygen in spinel oxide Li1+xTi2-xO4-delta thin films   The evolution from superconducting LiTi2O4-delta to insulating Li4Ti5O12 thin
films has been studied by precisely adjusting the oxygen pressure during the
sample fabrication process. In the superconducting LiTi2O4-delta films, with
the increase of oxygen pressure, the oxygen vacancies are filled, and the
c-axis lattice constant decreases gradually. With the increase of the oxygen
pressure to a certain critical value, the c-axis lattice constant becomes
stable, which implies that the Li4Ti5O12 phase comes into being. The process of
oxygen filling is manifested by the angular bright-field images of the scanning
transmission electron microscopy techniques. The temperature of
magnetoresistance changed from positive and negative shows a non-monotonous
behavior with the increase of oxygen pressure. The theoretical explanation of
the oxygen effects on the structure and superconductivity of LiTi2O4-delta has
also been discussed in this work.

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The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
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The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas