@article{oai:nagoya.repo.nii.ac.jp:00024550,
 author = {Maeda, Yusaku and Wakamatsu, Toru and Konishi, Ayako and Moriwake, Hiroki and Moriyoshi, Chikako and Kuroiwa, Yoshihiro and Tanabe, Kenji and Terasaki, Ichiro and Taniguchi, Hiroki},
 issue = {3},
 journal = {Physical Review Applied},
 month = {Mar},
 note = {In the present study, we demonstrate ferroelectricity in stuffed aluminate sodalites (Ca1−xSrx)8[AlO2]12(WO4)2 (x≤0.2) (C1−xSxAW). Pyroelectric measurements clarify switchable spontaneous polarization in polycrystalline C1−xSxAW, whose polarization values are on the order of 10^−2  μC/cm^2 at room temperature. A weak anomaly in the dielectric permittivity at temperatures near the ferroelectric transition temperature suggests improper ferroelectricity of C1−xSxAW for all investigated values of x. A comprehensive study involving synchrotron x-ray powder diffraction measurements, molecular dynamics simulations, and first-principles calculations clarifies that the ferroelectric phase transition of C1−xSxAW is driven by the freezing of the fluctuations of WO4 tetrahedra in the voids of an [AlO2]12^12− framework. The voltage response and electromechanical coupling factor of C1−xSxAW estimated from the present results indicate that this material exhibits excellent performance as a pyroelectric energy harvester, suggesting that aluminate sodalites exhibit great promise as a class of materials for highly efficient energy-harvesting devices.},
 pages = {034012--034012},
 title = {Improper Ferroelectricity in Stuffed Aluminate Sodalites for Pyroelectric Energy Harvesting},
 volume = {7},
 year = {2017}
}