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El origen del decaimiento de magnetización en las uniones de túneles dependientes de espín
McCartney1, Dunin-Borkowski, Scheinfein
1Center for Solid State Science, Department of Physics and Astronomy, Arizona State University, Tempe, AZ 85287-1704, USA. IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120-6099, USA.
Science (New York, N.Y.)
|November 13, 1999
Resumen
Las capas magnéticamente duras en las uniones de túneles dependientes de espín decaen debido a los campos de bordeado de las capas blandas. Esta inestabilidad amenaza futuras aplicaciones de dispositivos de almacenamiento de información.
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:
- Las uniones de túneles dependientes del espín son clave para el almacenamiento de información.
- La inestabilidad en la capa magnética dura causa la desintegración de la magnetización, lo que dificulta las aplicaciones del dispositivo.
Objetivo del estudio:
- Investigar la causa de la desintegración de la capa dura en las uniones de túneles dependientes del giro.
- Comprender el mecanismo detrás de la inestabilidad de la magnetización.
Principales métodos:
- Microscopía electrónica Lorentz con microscopía electrónica Lorentz.
- Simulaciones micromagnéticas de las simulaciones.
Principales resultados:
- El decaimiento de la capa dura se origina en los campos de franjas de las paredes del dominio magnético en la capa blanda.
- El movimiento de la pared del dominio induce el cambio estadístico de los momentos magnéticos en los granos de la capa dura.
- Se observó un desorden progresivo y la desmagnetización de la capa dura.
Conclusiones:
- Los campos de borde de las paredes de dominio de la capa blanda son responsables de la inestabilidad de la capa dura.
- Este mecanismo limita la fiabilidad de las uniones de túneles dependientes del giro para el almacenamiento de datos.
- Se necesitaban más investigaciones para mitigar este decaimiento para aplicaciones prácticas.
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