Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Andreev reflection observation in Nb/FeSi/Nb and Nb/FeSi/Si/Nb Josephson
  junctions   Electrical properties of Josephson junctions Nb/FeSi/Nb with
superconductor/ferromagnet (S/F)interfaces are presented. Due to Andreev
reflection the nearly exact quadruple enhancement of the tunnel junction
differential conductance compared with that of the normal state was achieved.
The transparency of the S/F interfaces in our junctions was estimated to be
close to unity. This almost ideal value is obtained due to the use of a very
smooth amorphous magnetic FeSi alloy for the barrier preparation. The real
structure of the Nb/FeSi/Nb tunnel junction is described as a S/F/I/F/S
junction. Also Nb/FeSi/Si/Nb Josephson junctions were investigated and the
results found on these junctions confirm the effects observed in Nb/FeSi/Nb.

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The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
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The categories of this paper are: adap-org
16
The categories of this paper are: stat