Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-filtered Edge States with an Electrically Tunable Gap in a
  Two-Dimensional Topological Crystalline Insulator   Three-dimensional topological crystalline insulators were recently predicted
and observed in the SnTe class of IV-VI semiconductors, which host metallic
surface states protected by crystal symmetries. In this work, we study thin
films of these materials and expose their potential for device applications. We
demonstrate that thin films of SnTe and Pb(1-x)Sn(x)Se(Te) grown along the
(001) direction are topologically nontrivial in a wide range of film thickness
and carry conducting spin-filtered edge states that are protected by the (001)
mirror symmetry via a topological invariant. Application of an electric field
perpendicular to the film will break the mirror symmetry and generate a band
gap in these edge states. This functionality motivates us to propose a novel
topological transistor device, in which charge and spin transport are maximally
entangled and simultaneously controlled by an electric field. The high on/off
operation speed and coupling of spin and charge in such a device may lead to
electronic and spintronic applications for topological crystalline insulators.

37
The categories of this paper are: supr-con
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an