Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-based Mach-Zehnder interferometry in topological insulator p-n
  junctions   A p-n junction, an interface between two regions of a material populated with
carriers of opposite charge, is a basic building block of solid state
electronic devices. From the fundamental physics perspective, it often serves
as a tool to reveal the unconventional transport behavior of novel materials.
In this work, we show that a p-n junction made from a three dimensional
topological insulator (3DTI) in a magnetic field realizes an electronic
Mach-Zehnder interferometer with virtually perfect visibility. This is owed to
the confinement of the topological Dirac fermion state to a closed
two-dimensional surface, which offers the unprecedented possibility of
utilizing external fields to design networks of chiral modes wrapping around
the bulk in closed trajectories, without the need of complex constrictions or
etching. Remarkably, this junction also acts as a spin filter, where the path
of the particle is tied to the direction of spin propagation. It therefore
constitutes a novel and highly tunable spintronic device where spin polarized
input and output currents are naturally formed and could be accessed and
manipulated seperately.

10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc