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La magnetorresistencia colosal en Mn2+ oxypnictides es NdMnAsO{1-x) F{x)
Eve J Wildman1, Janet M S Skakle, Nicolas Emery
1Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, UK.
Journal of the American Chemical Society
|May 11, 2012
Resumen
Se observó una magnetorresistencia colosal en un nuevo material NdMnAsO{1-x) F{x). Este descubrimiento en oxypnictides antiferromagnéticos podría allanar el camino para dispositivos avanzados de memoria magnética.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
Sus antecedentes:
- La magnetorresistencia colosal (CMR) es un fenómeno raro en el que la resistividad del material disminuye drásticamente bajo un campo magnético.
- Los materiales CMR tienen potencial para la próxima generación de dispositivos de memoria.
Objetivo del estudio:
- Para investigar la colosal magnetorresistencia en la relativamente inexplorada familia de los oxipnictidos Mn(2+).
- Para explorar NdMnAsO{1-x) F{x) como un potencial material CMR.
Principales métodos:
- Síntesis de nuevos compuestos NdMnAsO{1-x) F{x}.
- Caracterización de la resistividad electrónica bajo campos magnéticos variables.
Principales resultados:
- Se observó con éxito una magnetorresistencia colosal en NdMnAsO{1-x) F{x).
- El efecto CMR surge de la interacción entre las fases aislante y semiconductora bajo campos magnéticos.
Conclusiones:
- NdMnAsO{1-x) F{x) exhibe CMR, impulsado por fases magnéticas y electrónicas en competencia.
- Esta clase de materiales ofrece una nueva vía para el desarrollo de tecnologías avanzadas de memoria magnética.
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