Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Topological states and phase transitions in Sb$_2$Te$_3$-GeTe
  multilayers   Topological insulators (TIs) are bulk insulators with exotic 'topologically
protected' surface conducting modes. It has recently been pointed out that when
stacked together, interactions between surface modes can induce diverse phases
including the TI, Dirac semimetal, and Weyl semimetal. However, currently a
full experimental understanding of the conditions under which topological modes
interact is lacking. Here, working with multilayers of the TI Sb$_2$Te$_3$ and
the band insulator GeTe, we provide experimental evidence of a multiple
topological modes in a single Sb$_2$Te$_3$-GeTe-Sb$_2$Te$_3$ structure.
Furthermore, we show that reducing the thickness of the GeTe layer induces a
phase transition from a Dirac-like phase to a gapped phase. By comparing
different multilayer structures we demonstrate that this transition occurs due
to the hybridisation of states associated with different TI films. Our results
demonstrate that the Sb$_2$Te$_3$-GeTe system offers strong potential towards
manipulating topological states as well as towards controlledly inducing
various topological phases.

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The categories of this paper are: q-bio
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The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
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The categories of this paper are: stat
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The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
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The categories of this paper are: physics
0
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: q-fin
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The categories of this paper are: hep-th
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The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: cmp-lg