Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Interchangeability of Combined Piezoelectrooptic Effect in LiTaO3 and
  LiNbO3 Crystals   In the present paper the coefficients of piezooptic (PO), electrooptic (EO)
and combined piezoelectrooptic (PEO) effects for LiNbO3 and LiTaO3 crystals are
reported. It is shown that the combined PEO effect is interchangeable, i.e. its
coefficients determined independ-ently from the EO and PO experiments are the
same.

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The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: q-alg
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The categories of this paper are: comp-gas
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The categories of this paper are: patt-sol
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The categories of this paper are: supr-con
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The categories of this paper are: eess
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The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: funct-an