Dielectric Properties in CaCu3Ti4O12 Single Crystal at High Temperatures

• Published in: Ferroelectrics Vol. 402; no. 1; pp. 200 - 205
• Main Authors: Kawatani, K., Takesada, M., Fukunaga, M., Oda, M., Ido, M., Onodera, A.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Colchester Taylor & Francis Group 01.01.2010; Taylor & Francis
• Subjects: Anomalies; BOUNDARIES; CaCu; CERAMICS; Condensed matter: electronic structure, electrical, magnetic, and optical properties; COPPER OXIDE; crystal growth; dielectric anomaly; DIELECTRIC CONSTANT; Dielectric loss and relaxation; Dielectric properties; Dielectric properties of solids and liquids; Dielectrics; Dielectrics, piezoelectrics, and ferroelectrics and their properties; ELECTRICAL PROPERTIES; ELEVATED TEMPERATURE; Exact sciences and technology; Ferroelectric materials; giant susceptibility; GRAIN BOUNDARIES; INSULATION (ELECTRICAL); Origins; Permittivity (dielectric function); perovskite; phase transition; Physics; PROPERTIES; SINGLE CRYSTALS; Grain boundaries; dielectric anomaly; perovskite; Phase transformations; Dielectric properties; Polycrystals; Perovskites; High temperature; Calcium Copper Titanates Mixed; CaCu; O; Monocrystals; Ti; Dielectric losses; giant susceptibility; Anomaly; crystal growth; phase transition; Permittivity
• ISSN: 0015-0193; 1563-5112
• DOI: 10.1080/00150191003711376

High-temperature dielectric properties of perovskite-related CaCu 3 Ti 4 O 12 single and polycrystalline samples were studied. Both samples show a very similar high dielectric response, while the value of single crystal is about two times as large as those of polycrystalline ceramic samples. The dielectric constant shows a shoulder-like round anomaly around 600 K with increasing temperature, and a dielectric anomaly at 726 K for the present single crystal (732 K for ceramic samples). The present evidence means that a structural phase transition occurs in CaCu 3 Ti 4 O 12 at 726 K. The origin of high dielectric response is not related to an extrinsic one due to grains and grain boundary layers.