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Enlace de túnel totalmente antiferromagnético con ayuda de torsión en el límite atómico
Yuliang Chen1, Kartik Samanta2,3, Naafis A Shahed2,3
1Max Planck Institute of Microstructure Physics, Halle, Germany.
Nature
|August 14, 2024
Resumen
Los investigadores desarrollaron un nuevo método de torsión para las uniones de túneles totalmente antiferromagnéticos utilizando antiferromagnetos 2D. Esta técnica logra una alta relación de magnetorresistencia de túnel no volátil, allanando el camino para los dispositivos de almacenamiento magnético de límite atómico.
Área de la Ciencia:
- Física de la materia condensada
- Ciencias de los materiales
- La tecnología Spintronics
Sus antecedentes:
- La espintrónica antiferromagnética ofrece el potencial para dispositivos de información ultrarrápidos de alta densidad.
- Los materiales antiferromagnéticos se utilizan cada vez más en las uniones de túneles magnéticos (MTJ).
Objetivo del estudio:
- Para demostrar una estrategia de torsión para crear uniones de túneles totalmente antiferromagnéticos a escala atómica.
- Investigar las propiedades de la magnetorresistencia de túnel (TMR) de los materiales antiferromagnéticos 2D retorcidos.
Principales métodos:
- Construir uniones de túnel totalmente antiferromagnéticas girando las dos capas del antiferromagnético 2D CrSBr.
- Medición de la relación de magnetorresistencia de túnel no volátil (TMR) en el campo cero.
- Analizando la dependencia de TMR en el ángulo de giro y la temperatura.
Principales resultados:
- Se logró una relación de TMR no volátil >700% en campo cero utilizando bicapas retorcidas de CrSBr.
- Se ha demostrado que la TMR se origina en túneles coherentes acumulativos a través de monocapas de CrSBr.
- Se observó una dependencia de la temperatura significativamente menor de la TMR en las uniones retorcidas en comparación con las no retorcidas.
Conclusiones:
- Una estrategia de torsión permite la construcción de uniones de túnel totalmente antiferromagnéticas en el límite atómico.
- Las uniones de túneles antiferromagnéticos retorcidos exhiben altas relaciones de TMR y una mejor estabilidad térmica.
- Este enfoque avanza el almacenamiento de información magnética no volátil hacia el límite atómicamente delgado.
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