Specific-heat evidence for strong electron correlations in the thermoelectric material(Na,Ca)Co2O4

  title={Specific-heat evidence for strong electron correlations in the thermoelectric material(Na,Ca)Co2O4},
  author={Yoichi Ando and N. Miyamoto and Kouji Segawa and T. Kawata and Ichiro Terasaki},
  journal={Physical Review B},
The specific heat of $(\mathrm{N}\mathrm{a},\mathrm{C}\mathrm{a}){\mathrm{Co}}_{2}{\mathrm{O}}_{4}$ is measured at low-temperatures to determine the magnitude of the electronic specific-heat coefficient $\ensuremath{\gamma},$ in an attempt to gain an insight into the origin of the unusually large thermoelectric power of this compound. It is found that $\ensuremath{\gamma}$ is as large as $\ensuremath{\sim}48 {\mathrm{m}\mathrm{J}/\mathrm{m}\mathrm{o}\mathrm{l}\mathrm{K}}^{2},$ which is an order… 
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