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Bistabilidad en antiferromagnetos a escala atómica.
Sebastian Loth1, Susanne Baumann, Christopher P Lutz
1IBM Research Division, Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA. sebastian.loth@mpsd.cfel.de
Science (New York, N.Y.)
|January 17, 2012
Resumen
Los investigadores demuestran el control del magnetismo a escala atómica utilizando nanoestructuras de hierro (Fe). Estas estructuras exhiben estados magnéticos estables, lo que permite el almacenamiento de datos densos y no volátiles con capacidades de conmutación eléctrica.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- La miniaturización de los dispositivos de almacenamiento de datos requiere un control del magnetismo a escala atómica.
- Los materiales antiferromagnéticos ofrecen potencial para el almacenamiento de información de alta densidad.
Objetivo del estudio:
- Para investigar las propiedades magnéticas de las nanoestructuras antiferromagnéticas de pocos átomos.
- Para demostrar la conmutación eléctrica y el almacenamiento de datos no volátiles a escala atómica.
Principales métodos:
- Fabricación de nanoestructuras de hierro (Fe) de pocos átomos en una superficie.
- Utilizando túneles polarizados por espín para detectar estados magnéticos.
- Manipulación eléctrica de los estados magnéticos con una precisión de nanosegundos.
- Observando el túnel cuántico de la magnetización en pequeñas nanoestructuras.
Principales resultados:
- Las nanoestructuras antiferromagnéticas exhiben dos estados de Néel estables a bajas temperaturas.
- Túneles cuánticos de magnetización observados en las estructuras más pequeñas.
- La conmutación eléctrica entre estados magnéticos se logra con una velocidad de nanosegundos.
- Se ha demostrado el almacenamiento de información densa no volátil mediante la adaptación de nanoestructuras.
Conclusiones:
- El control a escala atómica del antiferromagnetismo es alcanzable.
- Los fenómenos cuánticos influyen en las transiciones de estado magnético en las nanoestructuras.
- El control eléctrico permite aplicaciones prácticas en el almacenamiento de datos densos y no volátiles.
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