Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tunneling processes into localized subgap states in superconductors   We combine scanning-tunneling-spectroscopy experiments probing magnetic
impurities on a superconducting surface with a theoretical analysis of the
tunneling processes between (superconducting) tip and substrate. We show that
the current is carried by single-electron tunneling at large tip-substrate
distances and Andreev reflections at smaller distances. The single-electron
current requires relaxation processes between the impurity-induced Shiba bound
state and the quasiparticle continuum, allowing us to extract information on
such relaxation processes from our analysis.

16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex