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El ferromagnetismo en las superredes LaFeO3-LaCrO3
1The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567, Japan.
Science (New York, N.Y.)
|May 22, 1998
Resumen
El orden de giro ferromagnético se logró en superrías LaCrO3-LaFeO3. Las capas artificiales de iones Fe3+ y Cr3+ permitieron el acoplamiento ferromagnético, superando los desafíos anteriores en los materiales Fe-O-Cr.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- Química del estado sólido.
Sus antecedentes:
- El acoplamiento ferromagnético entre los iones Fe3+ y Cr3+ a través del oxígeno está predicho por teorías establecidas (reglas de Anderson, Goodenough, Kanamori).
- Estudios previos sobre compuestos Fe-O-Cr se vieron obstaculizados por la distribución aleatoria de iones, lo que impidió la observación del ferromagnetismo.
Objetivo del estudio:
- Para lograr un orden de espín ferromagnético en superretas de LaCrO3-LaFeO3.
- Para superar las limitaciones de la colocación aleatoria de iones en los sistemas Fe-O-Cr.
Principales métodos:
- Fabricación de superredes artificiales con iones Fe3+ y Cr3+ en capas con precisión.
- Crecimiento de superredes a lo largo de la dirección cristalográfica [111].
Principales resultados:
- Realización exitosa del orden de espín ferromagnético en las superretillas LaCrO3-LaFeO3 diseñadas.
- Demostración de que la estratificación controlada supera el problema de la distribución aleatoria de iones.
Conclusiones:
- Las superredes artificiales proporcionan una ruta viable para lograr el acoplamiento ferromagnético previsto en los sistemas Fe-O-Cr.
- La estructura de superretícula en capas [111] es clave para observar el ferromagnetismo en estos materiales.
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