Relation between structural instabilities in EuTiO3 and SrTiO3

Article

关键词: K PHASE-TRANSITION;    SOFT PHONON MODES;    STRONTIUM-TITANATE;    HEAT MEASUREMENTS;    FERROELECTRICITY;    POLARIZABILITY;    SCATTERING;    RESONANCE;    BEHAVIOR;   

DOI  :  10.1103/PhysRevB.83.212102

来源: SCIE

【 摘 要 】

Specific heat measurements and theoretical calculations reveal an intimate analogy between EuTiO3 and SrTiO3. For EuTiO3, a hitherto unknown specific heat anomaly is discovered at temperatures T-A = 282(1) K, which is analogous to the well-known specific heat anomaly of SrTiO3 at the temperature T-A = 105K caused by an antiferrodistortive transition. Because the zone center soft phonon mode observed in both systems can be modeled with the same parameters, we ascribe the new 282(1) K instability of EuTiO3 to an antiferrodistortive phase transition. The higher transition temperature of EuTiO3 as compared to SrTiO3 results from spin-phonon coupling.

【 授权许可】

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