Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatially inhomogeneous discrete states of a superconductor upon
  injection of nonequilibrium quasiparticles from a point contact with a normal
  metal   The current-voltage characteristics (IVC) of $S-c-N$ point contacts of
superconductors with a small coherence length ${{\xi}_{0}}$ reveal steps with
discrete values of the differential resistance. This peculiarity is associated
with a transition of the contact region of the superconductor to a spatially
inhomogeneous state under the influence of the current injection of
nonequilibrium quasiparticles penetrating the superconductor to a depth
${{l}_{E}}$ . The role of the relaxation of the disbalance between the
occupancies of electron- and hole-like branches of the quasiparticle spectrum
is manifested in the displacement of the position of the singularities on the
IVC towards higher energies upon an increase in the magnetic field and/or
temperature. This effect was observed in superconductors with different ratios
of the contact diameter $d$ and ${{\xi}_{0}}$ or ${{l}_{E}}$ in the series $Ta\
(d\ll {{\xi}_{0}},\ {{l}_{E}})\to NbS{{e}_{2}}$, $N{{b}_{3}}Sn\ (d\gtrsim
{{\xi}_{0}},\ {{l}_{E}})\to
YB{{a}_{1.25}}S{{r}_{0.75}}C{{u}_{3}}{{O}_{7-\delta}}(d\gg {{\xi}_{0}},\
{{l}_{E}})$. Apparently, a jumplike displacement of the boundary between
regions with suppressed and equilibrium values of the energy gap near the
contact is responsible for the oscillations observed on the IVC of point
contacts between single crystals of high- temperature superconductors (HTS) and
a normal metal. The resistance-periodic step-like structure of the IVC allows
us to estimate the penetration depth ${{l}_{E}}$ of the electric field in
$NbS{{e}_{2}}$ and $YBaSrCuO$.

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The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org