Low-temperature measurements of the specific heat capacity of a thick ferroelectric copolymer film of vinylidene fluoride and trifluoroethylene
R. W. Newsome Jr., S. Park, S.-W. Cheong, and E. Y. Andrei

{ The specific heat capacity, c$_{\rm{p}}$, of a 110 $\mu$m thick, and partially crystallized ($\sim $77$\%$), ferroelectric copolymer (PVDF/TrFE) film of vinylidene fluoride ($\sim $~$\mbox{75 mol\%}$) and trifluoroethylene ($\sim $ 25 mol$\%$) was measured from 2 to 20 K. The temperature dependence of c$_{\rm{p}}$/T$^{3}$ reveals a shallow hump, centered at $\mbox{$\sim$ 5 K}$, consistent with non-Debye behavior of semicrystalline materials. These c$_{\rm{p}}$ data were used, in conjunction with previous measurements of the pyroelectric coefficient, $|p'|$, to infer the temperature profile of the macroscopic Gr\"{u}neisen parameter, based on ratios of $|p'|$/c$_{\rm{p}}$. Comparisons with similar data for PVDF are consistent with a correlation between anharmonicity of the interaction potential and excess specific heat capacity.}

© 2008 The American Physical Society.