Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Origin of charge transfer and enhanced electron-phonon coupling in
  single unit-cell FeSe films on SrTiO3   Interface charge transfer and electron-phonon coupling have been suggested to
play a crucial role in the recently discovered high-temperature
superconductivity of single unit-cell FeSe films on SrTiO3. However, their
origin remains elusive. Here, using ultraviolet photoemission spectroscopy
(UPS) and element-sensitive X-ray photoemission spectroscopy (XPS), we identify
the strengthened Ti-O bond that contributes to the interface enhanced
electron-phonon coupling and unveil the band bending at the FeSe/SrTiO3
interface that leads to the charge transfer from SrTiO3 to FeSe films. We also
observe band renormalization that accompanies the onset of superconductivity.
Our results not only provide valuable insights into the mechanism of the
interface-enhanced superconductivity, but also point out a promising route
towards designing novel superconductors in heterostructures with band-bending
induced charge transfer and interfacial enhanced electron-phonon coupling.

26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg