Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Piezo-ferroelectrics: Pressure-induced phase transitions in
  Pb(Zr1-xTix)O3 (PZT)   Piezoelectric PZT solid solutions were studied as a function of pressure and
temperature. Moderate pressure is found to induce phase transitions to
monoclinic phases (Cm,Cc) for Ti-rich PZT, which are the same ferroelectric
phases responsible for the high piezoelectric properties of the MPB. The
following transformation sequence P4mm -> Cm -> Cc -> F1 -> F-1 was identified
upon increasing pressure. Compression behaviour is dominated by: (1) a rotation
and a reduction of the spontaneouspolarization and (2) octahedral tilting
leading to unit cell doubling. Future studies as a function of pressure,
temperature and electric field on single crystals of heterovalent relaxor
ferroelectric isotypes of PZT are proposed in order to better understand these
potentially technologically-important piezoferroelectric materials.

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The categories of this paper are: chem-ph
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The categories of this paper are: math
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The categories of this paper are: q-fin
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The categories of this paper are: hep-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
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The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg