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Activación del ferromagnetismo de alto T (C) en ZnO dopado con Mn2+ utilizando aminas
Kevin R Kittilstved1, Daniel R Gamelin
1Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, USA.
Journal of the American Chemical Society
|April 14, 2005
Resumen
El ferromagnetismo a alta temperatura en el óxido de zinc dopado con manganeso (Mn2+:ZnO) se activa mediante la unión de aminas y la calcinación. Este proceso incorpora dopantes de tipo p, formando polarones magnéticos unidos e influyendo en la sensibilidad del ferromagnetismo a los defectos.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
- Semiconductor Spintronics es una tecnología de semiconductores.
Sus antecedentes:
- El ferromagnetismo de alta temperatura en semiconductores magnéticos diluidos como el óxido de zinc dopado con manganeso (Mn2+:ZnO) sigue siendo un área de investigación importante.
- Estudios anteriores han reportado diversas observaciones experimentales con respecto al ferromagnetismo en Mn2+:ZnO, lo que sugiere sensibilidad al procesamiento de materiales y defectos.
- Comprender los mecanismos que controlan el ferromagnetismo es crucial para el desarrollo de aplicaciones espintrónicas.
Objetivo del estudio:
- Investigar el papel de la unión y calcinación de aminas en la activación del ferromagnetismo en Mn2+:ZnO.
- Para dilucidar el mecanismo microscópico responsable del ferromagnetismo observado.
- Para explicar la variabilidad en los resultados experimentales para Mn2+:ZnO.
Principales métodos:
- Síntesis experimental y caracterización del óxido de zinc dopado con manganeso (Mn2+:ZnO).
- La unión de aminas y el posterior tratamiento de calcinación de muestras de Mn2+:ZnO.
- Análisis de las propiedades magnéticas y correlación con los defectos de los materiales.
Principales resultados:
- El ferromagnetismo en Mn2+:ZnO puede activarse con éxito a través de la unión de aminas y la calcinación.
- Esta activación está relacionada con la incorporación de dopantes de tipo p no compensados en la red de ZnO.
- Los datos experimentales se alinean con un mecanismo que implica la formación de polarones magnéticos unidos.
Conclusiones:
- El ferromagnetismo en Mn2+:ZnO es críticamente dependiente de la presencia de defectos más allá de los dopantes magnéticos.
- El estudio proporciona información sobre los diversos resultados experimentales reportados para Mn2+:ZnO.
- El dopaje de tipo p inducido por aminas ofrece una vía para controlar y activar el ferromagnetismo en este material.
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