Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Theoretical Prediction of Topological Insulators in Thallium-based
  III-V-VI$_2$ Ternary Chalcogenides   We predict a new class of three dimensional topological insulators in
thallium-based III-V-VI$_2$ ternary chalcogenides, including TlBiQ$_2$ and
TlSbQ$_2$ (Q = Te, Se and S). These topological insulators have robust and
simple surface states consisting of a single Dirac cone at the $\Gamma$ point.
The mechanism for topological insulating behavior is elucidated using both
first principle calculations and effective field theory models. Remarkably, one
topological insulator in this class, TlBiTe$_2$ is also a superconductor when
doped with $p$-type carriers. We discuss the possibility that this material
could be a topological superconductor. Another material TlSbS$_2$ is on the
border between topological insulator and trivial insulator phases, in which a
topological phase transition can be driven by pressure.

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The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
6
The categories of this paper are: astro-ph