Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electrically switchable tunneling across a graphene pn junction:
  evidence for canted antiferromagnetic phase in $\nu=0$ state   The ground state of a graphene sheet at charge neutrality in a perpendicular
magnetic field remains enigmatic, with various experiments supporting canted
antiferromagnetic, bond ordered, and even charge density wave phases. A
promising avenue to elucidating the nature of this state is to sandwich it
between regions of different filling factors, and study spin-dependent
tunneling across the edge modes at the interfaces. Here we report on tunnel
transport through a $\nu=0$ region in a graphite-gated, hexagonal boron nitride
($hBN$) encapsulated monolayer graphene device, with the $\nu=0$ strip
sandwiched by spin-polarized $\nu=\pm1$ quantum Hall states. We observe finite
tunneling ($t \sim 0.3-0.6$) between the $\nu=\pm1$ edges at not too small
magnetic fields ($B>3T$) and low tunnel bias voltage ($<30-60\mu V$), which is
surprising because electrons at the edge states nominally have opposite spins.
Hartree-Fock calculations elucidate these phenomena as being driven by the
formation of a CAF order parameter in the $\nu=0$ region at zero bias (for wide
enough junctions) leading to non-orthogonal spins at the edges. Remarkably,
this tunneling can be controllably switched off by increasing bias; bias
voltage leads to a pileup of charge at the junction, leading to a collapse of
the CAF order and a suppression of the tunneling.

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The categories of this paper are: math-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
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The categories of this paper are: q-bio
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The categories of this paper are: alg-geom
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The categories of this paper are: hep-lat
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The categories of this paper are: plasm-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-ph
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The categories of this paper are: cs
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The categories of this paper are: physics
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The categories of this paper are: math
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn