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Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
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Magnetorresistencia a temperatura ambiente en una unión de túnel totalmente antiferromagnética
Peixin Qin1, Han Yan1, Xiaoning Wang1
1School of Materials Science and Engineering, Beihang University, Beijing, China.
Nature
|January 18, 2023
Resumen
Los investigadores desarrollaron uniones de túneles antiferromagnéticos a temperatura ambiente utilizando un nuevo efecto de sesgo de intercambio. Estos dispositivos exhiben una gran magnetorresistencia, allanando el camino para las tecnologías de memoria ultrarrápida de próxima generación.
Área de la Ciencia:
- Física de la materia condensada
- Ciencias de los materiales
- Tecnología de la información
Sus antecedentes:
- La espintrónica antiferromagnética ofrece el potencial para dispositivos de información ultrarrápidos de alta densidad.
- Las aplicaciones prácticas se ven obstaculizadas por las salidas eléctricas a baja temperatura ambiente.
Objetivo del estudio:
- Para investigar un efecto de sesgo de intercambio de temperatura ambiente entre antiferromagnetos colineares (MnPt) y no colineares (Mn3Pt).
- Desarrollar uniones de túnel totalmente antiferromagnéticas con magnetoresistencia mejorada.
Principales métodos:
- Utilizó un efecto de sesgo de intercambio exótico entre MnPt y Mn3Pt.
- Las uniones de túneles son totalmente antiferromagnéticas.
- Realizó simulaciones de la dinámica del espín atómico y cálculos de los primeros principios.
Principales resultados:
- Se logró un efecto de sesgo de intercambio de temperatura ambiente entre MnPt y Mn3Pt.
- Se ha demostrado una magnetorresistencia no volátil a temperatura ambiente de hasta el 100% en las uniones del túnel.
- Se identificaron giros de interfaz no compensados en MnPt como la fuente del sesgo de intercambio.
- Determinación de la polarización de espín en el espacio de impulso de Mn3Pt como origen de la magnetorresistencia.
Conclusiones:
- Las uniones de túnel totalmente antiferromagnéticas desarrolladas exhiben una magnetorresistencia significativa a temperatura ambiente.
- Estos dispositivos tienen campos perdidos que casi desaparecen y dinámicas de giro a nivel de terahertz.
- Potencial para la próxima generación de dispositivos de memoria altamente integrados y ultrarrápidos.
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