Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: de Gennes-Saint-James resonant transport in Nb/GaAs/AlGaAs
  heterostructures   Resonant transport is demonstrated in a hybrid superconductor-semiconductor
heterostructure junction grown by molecular beam epitaxy on GaAs. This
heterostructure realizes the model system introduced by de Gennes and
Saint-James in 1963 [P. G. de Gennes and D. Saint-James, Phys. Lett. {\bf 4},
151 (1963)]. At low temperatures a single marked resonance peak is shown
superimposed to the characteristic Andreev-dominated subgap conductance. The
observed magnetotransport properties are successfully analyzed within the
random matrix theory of quantum transport, and ballistic effects are included
by directly solving the Bogoliubov-de Gennes equations.

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The categories of this paper are: math
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
3
The categories of this paper are: physics