Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Purely in-plane ferroelectricity in monolayer SnS at room temperature   2D van der Waals ferroelectric semiconductors have emerged as an attractive
building block with immense potential to provide multifunctionality in
nanoelectronics. Although several accomplishments have been reported in
ferroelectric resistive switching for out-of-plane 2D ferroelectrics down to
the monolayer, a purely in-plane ferroelectric has not been experimentally
validated at the monolayer thickness. Herein, a micrometer-size monolayer SnS
is grown on mica by physical vapor deposition, and in-plane ferroelectric
switching is demonstrated with a two-terminal device at room temperature (RT).
SnS has been commonly regarded to exhibit the odd-even effect, where the
centrosymmetry breaks only in the odd-number layers to exhibit
ferroelectricity. Remarkably, however, a robust RT ferroelectricity exists in
SnS below a critical thickness of 15 layers with both an odd and even number of
layers. The lack of the odd-even effect probably originates from the
interaction with the mica substrate, suggesting the possibility of controlling
the stacking sequence of multilayer SnS, going beyond the limit of
ferroelectricity in the monolayer. This work will pave the way for nanoscale
ferroelectric applications based on SnS as a new platform for in-plane
ferroelectrics.

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The categories of this paper are: astro-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: econ
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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: math-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: gr-qc
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The categories of this paper are: cmp-lg
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
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The categories of this paper are: q-alg