Mapping chemical disorder and ferroelectric distortions in the double perovskite compound Sr2-xGdxMnTiO6 by atomic resolution electron microscopy and spectroscopy

In this work we report a study of the chemical and structural order of the double perovskite compound Sr2-xGdxMnTiO6 for compositions x = 0, 0.25, 0.5, 0.75, and 1. A noticeable disorder at the B-site in the Mn and Ti sublattice is detected at the atomic scale by electron energy-loss spectroscopy fo...

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Detalles Bibliográficos
Autores: Biskup Zaja, Nevenko, Álvarez Serrano, Inmaculada, Veiga, María, Rivera Calzada, Alberto Carlos, Garcia Hernandez, Mar, Pennycook, Stephen J., Varela Del Arco, María
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/105022
Acceso en línea:https://hdl.handle.net/20.500.14352/105022
Access Level:acceso abierto
Palabra clave:538.9
Atomic resolution electron microscopy
Double perovskite
EELS
Electroresistance
Ferroelectric displacement
Física de materiales
2211 Física del Estado Sólido
Descripción
Sumario:In this work we report a study of the chemical and structural order of the double perovskite compound Sr2-xGdxMnTiO6 for compositions x = 0, 0.25, 0.5, 0.75, and 1. A noticeable disorder at the B-site in the Mn and Ti sublattice is detected at the atomic scale by electron energy-loss spectroscopy for all x values, resulting in Mn-rich and Ti-rich regions. For x >= 0.75, the cubic unit cell doubles and lowers its symmetry because of structural rearrangements associated with a giant ferroelectric displacement of the perovskite B-site cation. We discuss this finding in the light of the large electroresistance observed in Sr2-xGdxMnTiO6, x >= 0.75.