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Respuesta de campo heterogéneo de laminados polares jerárquicos en relajantes y ferroeléctricos
Hao Zheng1,2, Tao Zhou3, Dina Sheyfer2
1Materials Science Division, Argonne National Laboratory, Lemont, IL 60439, USA.
Science (New York, N.Y.)
|June 27, 2024
Resumen
Los investigadores descubrieron los laminados polares, los nanodominios polares organizados (PND), en las ferroeléctricas relajantes. Esta estructura jerárquica explica sus propiedades electromecánicas superiores y guía el diseño de materiales futuros.
Área de la Ciencia:
- Ciencias de los materiales
- Física de la materia condensada
- La cristalografía
Sus antecedentes:
- Los ferroeléctricos de Relaxor exhiben propiedades electromecánicas superiores.
- Comprender el papel de los nanodomainos polares (PND) en varias escalas de longitud es crucial.
- La formación a escala atómica y la disposición de largo alcance de los PND influyen en el comportamiento del material.
Objetivo del estudio:
- Investigar la organización a mesoescala de las PND en el relajador ferroeléctrico.
- Para aclarar la relación entre la disposición de PND y la respuesta electromecánica.
- Identificar los principios rectores para el diseño de materiales funcionales avanzados.
Principales métodos:
- Utilizó la nanodifracción coherente de rayos X.
- Se analizó el autoensamblaje de PND en laminados polares en PMN-0.32PT.
- Respuestas PND correlacionadas con las características de la cepa local y la pared del dominio.
Principales resultados:
- Se ha demostrado el autoensamblaje escalonado de PND en laminados polares unidireccionales.
- Reveló respuestas heterogéneas impulsadas por el campo eléctrico de PNDs intra e interlaminados.
- Se estableció un vínculo entre la tensión local, la naturaleza de la pared PND y las propiedades del material.
Conclusiones:
- La organización jerárquica de la red tiene un impacto crítico en las propiedades macroscópicas de los ferroeléctricos relajantes.
- Los laminados polares son las principales mesostructuras que rigen la respuesta electromecánica.
- Los hallazgos proporcionan principios de diseño para relajantes y otros materiales cuánticos.
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