Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First principles feasibility assessment of a topological insulator at
  the InAs/GaSb interface   First principles simulations are conducted to shed light on the question of
whether a two-dimensional topological insulator (2DTI) phase may be obtained at
the interface between InAs and GaSb. To this end, the InAs/GaSb interface is
compared and contrasted with the HgTe/CdTe interface. Density functional theory
(DFT) simulations of these interfaces are performed using a machine-learned
Hubbard U correction [npj Comput. Mater. 6, 180 (2020)]. For the HgTe/CdTe
interface our simulations show that band crossing is achieved and an inverted
gap is obtained at a critical thickness of 5.1 nm of HgTe, in agreement with
experiment and previous DFT calculations. In contrast, for InAs/GaSb the gap
narrows with increasing thickness of InAs; however the gap does not close for
interfaces with up to 50 layers (about 15 nm) of each material. When an
external electric field is applied across the InAs/GaSb interface, the
GaSb-derived valence band maximum is shifted up in energy with respect to the
InAs-derived conduction band minimum until eventually the bands cross and an
inverted gap opens. Our results show that it may be possible to reach the
topological regime at the InAs/GaSb interface under the right conditions.
However, it may be challenging to realize these conditions experimentally,
which explains the difficulty of experimentally demonstrating an inverted gap
in InAs/GaSb.

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The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg