Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Terahertz spectroscopy of an electron-hole bilayer system in AlN/GaN/AlN
  quantum wells   We describe studies on the nanoscale transport dynamics of carriers in
strained AlN/GaN/AlN quantum wells: an electron-hole bilayer charge system with
large difference in transport properties between the two charge layers. From
electronic band diagram analysis, the presence of spatially separated
two-dimensional electron and hole charge layers is predicted at opposite
interfaces. Since these charge layers exhibit distinct spectral signatures at
terahertz frequencies, a combination of terahertz and far-infrared spectroscopy
enables us to extract (a) individual contributions to the total conductivity,
as well as (b) effective scattering rates for charge-carriers in each layer.
Furthermore, by comparing direct-current and terahertz extracted conductivity
levels, we are able to determine the extent to which structural defects affect
charge transport. Our results evidence that (i) a non-unity Hall-factor and
(ii) the considerable contribution of holes to the overall conductivity, lead
to a lower apparent mobility in Hall-effect measurements. Overall, our work
demonstrates that terahertz spectroscopy is a suitable technique for the study
of bilayer charge systems with large differences in transport properties
between layers, such as quantum wells in III-Nitride semiconductors.

8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph