Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Zero-energy bound state at the interface between an $s$-wave
  superconductor and a disordered normal metal with repulsive electron-electron
  interactions   In recent years, there has been a renewed interest in the proximity effect
due to its role in the realization of topological superconductivity. Here, we
study a superconductor--normal metal proximity system with repulsive
electron-electron interactions in the normal layer. It is known that in the
absence of disorder or normal reflection at the superconductor--normal metal
interface, a zero-energy bound state forms and is localized to the interface
[Fauchere et al., Phys. Rev. Lett. 82, 3336 (1999)]. Using the quasiclassical
theory of superconductivity, we investigate the low-energy behavior of the
density of states in the presence of finite disorder and an interfacial
barrier. We find that as the mean free path is decreased, the zero-energy peak
in the density of states is broadened and reduced. In the quasiballistic limit,
the bound state eliminates the minigap pertinent to a noninteracting normal
layer and a distinct peak is observed. When the mean free path becomes
comparable to the normal layer width, the zero-energy peak is strongly
suppressed and the minigap begins to develop. In the diffusive limit, the
minigap is fully restored and all signatures of the bound state are eliminated.
We find that an interfacial potential barrier does not change the functional
form of the density of states peak but does shift this peak away from zero
energy.

20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org