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Semi-metalicidad a temperatura ambiente en una aleación de La(Mn,Zn)AsO a través de las sustituciones de elementos
Xingxing Li1, Xiaojun Wu, Jinlong Yang
1Hefei National Laboratory for Physical Science at the Microscale, ‡CAS Key Laboratory of Materials for Energy Conversion and Department of Materials Science and Engineering, and §Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China , Hefei, Anhui 230026, China.
Journal of the American Chemical Society
|March 29, 2014
Resumen
Los investigadores diseñaron un nuevo material semimetálico para dispositivos espintrónicos. Las sustituciones de elementos en La(Mn0.5Zn0.5)AsO crean un amplio espacio semimetálico y una alta temperatura de Curie, mejorando el rendimiento del dispositivo espintrónico.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- Química del estado sólido.
Sus antecedentes:
- El desarrollo de dispositivos espintrónicos de alto rendimiento requiere materiales con propiedades específicas como una alta temperatura de Curie, amplias brechas semimetálicas y una gran anisotropía magnética.
- Los materiales actuales a menudo no alcanzan estas características ideales, lo que hace necesaria la exploración de nuevos compuestos.
Objetivo del estudio:
- Diseñar un material práctico semimetálico con propiedades deseables para aplicaciones espintrónicas.
- Para investigar los efectos de las sustituciones de elementos en las propiedades electrónicas y magnéticas de las capas La(Mn0.5Zn0.5)AsO.
Principales métodos:
- Los cálculos de los primeros principios se emplearon para diseñar y analizar el material.
- Las sustituciones de elementos (dopaje) se introdujeron sistemáticamente en la aleación La(Mn0.5Zn0.5) AsO.
- Las simulaciones de Monte Carlo basadas en el modelo de Ising se utilizaron para predecir la temperatura de Curie.
Principales resultados:
- La inmaculada aleación La(Mn0.5Zn0.5)AsO es un semiconductor antiferromagnético.
- El agujero o el dopaje de electrones indujo la semimetallicidad con una brecha semimetálica significativa de 0,74 eV.
- Las temperaturas de Curie predichas alcanzaron 475 K (25% de dopaje de Ca) y 600 K (50% de dopaje de H).
- La aleación dopada exhibe una gran energía de anisotropía magnética, que excede a la de la mayor parte de Fe, Co y Ni.
Conclusiones:
- El La(Mn0.5Zn0.5) AsO sustituido por elementos es un candidato prometedor para dispositivos espintrónicos de alto rendimiento.
- El material diseñado demuestra una combinación favorable de un amplio espacio semimetálico, una alta temperatura de Curie y una gran anisotropía magnética.
- Este trabajo proporciona una vía viable para el desarrollo de materiales espintrónicos avanzados.
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