Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Robust propagating in-gap modes due to spin-orbit domain walls in
  graphene   Recent experimental progress in designing electronic states in layered
heterostructures raises questions about inducing topological states in
inhomogeneous systems. In particular, it has become clear that there is a
delicate interplay of multiple spin-orbit terms induced in graphene on
incommensurate transition metal dichalcogenide substrates, so that nano- to
mesoscopic domains of different spin-orbit and mass values may form. We
therefore investigate various types of domain walls in graphene looking for
robust propagating electronic states, first by finding the states via
analytical and topological arguments in the low-energy theory, and then
studying their robustness to symmetry breaking and lattice backscattering
effects in a tight-binding model.
  Surprisingly, we find that a sign-changing domain wall in Valley-Zeeman (VZ)
spin-orbit coupling binds two robust Kramers pairs within the bulkgap opened
due to a simultaneous presence of Rashba (R) coupling. We show the relation of
these modes to a domain wall in gating of bilayer graphene. In a contrasting
example, a sign-changing Kane-Mele (KM) spin-orbit coupling domain wall between
two domains in the topological insulator (TI) phase, equivalent to two copies
of a TI edge, has two pairs of helical modes that are stable to intervalley
scattering, but not stable to breaking $S_z$ symmetry, e.g., by a Rashba term.
Nevertheless, there are also higher excited modes on a smooth KM domain wall
which mimic Landau-levels of free spinless graphene. We also introduce a domain
wall by rotating the spin direction of the Kane-Mele term in a spiral, and
analytically explain the closing bulkgap and the lack of in-gap modes. We
discuss the possible spectroscopic and transport signatures in
heterostructures.

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The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
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The categories of this paper are: q-fin
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
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The categories of this paper are: hep-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: chem-ph
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The categories of this paper are: funct-an
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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn