Glasslike thermal properties of antiferroelectric PbZr O 3 at low temperatures
1984; American Physical Society; Volume: 30; Issue: 11 Linguagem: Inglês
10.1103/physrevb.30.6555
ISSN1095-3795
Autores Tópico(s)Material Dynamics and Properties
ResumoSpecific-heat and thermal-conductivity data (1.7---40 K) are reported for the first time on ceramic samples of the antiferroelectric PbZr${\mathrm{O}}_{3}$. A linear term in the specific heat is resolved below 3 K, and the thermal conductivity displays a quadratic temperature dependence below 4 K. The coefficients of these glasslike properties agree with those for amorphous solids, and the data suggest a plateau in the thermal conductivity above 40 K of \ensuremath{\sim}10 mW ${\mathrm{cm}}^{\ensuremath{-}1}$${\mathrm{K}}^{\ensuremath{-}1}$. A large maximum in $\frac{C}{{T}^{3}}$ at 14 K can be represented by two Einstein terms (44.1 and 25.0 ${\mathrm{cm}}^{\ensuremath{-}1}$), and the fitted Debye temperature (391 K) agrees well with the elastic value (396 K). A review of the glasslike properties observed in ferroelectric-type materials is given, and it is concluded that glasslike behavior is intimately associated with a spontaneous polarization (on one or two sublattices), irrespective of domain walls or ceramic grain boundaries.
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