Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Majorana Fermions and Multiple Topological Phase Transition in Kitaev
  Ladder Topological Superconductors   Motivated by the InSb nanowire superconductor system, we investigate a system
where one-dimensional topological superconductors are placed in parallel. It
would be simulated well by a ladder of the Kitaev chains. The system undergoes
multiple topological phase transitions, where the number of Majorana fermions
changes as a function of the interchain superconducting pairings. We
analytically determine the topological phase diagram by explicitly calculating
the topological number and the band structure. They show even-odd effects with
respect to the number of legs of the ladder. When the relative phase between
the inter- and intrachain superconducting pairings is 0 or $\pi$, the system
belongs to the class BDI characterized by the $\mathbb{Z}$ index, and otherwise
it belongs to the class D characterized by the $\mathbb{Z}_2$ index. This
topological class change would be caused by applying the Josephson current or
an external magnetic field, and could be observed by measuring the zero-bias
differential conductance.

27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
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The categories of this paper are: q-fin
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
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The categories of this paper are: bayes-an
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The categories of this paper are: adap-org
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The categories of this paper are: cmp-lg
2
The categories of this paper are: math