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El ferromagnetismo inducido eléctricamente a temperatura ambiente en dióxido de titanio dopado con cobalto
1Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
Science (New York, N.Y.)
|May 28, 2011
Resumen
El ferromagnetismo a temperatura ambiente fue inducido en (Ti,Co) O(2) utilizando el efecto de campo eléctrico. Esto demuestra un camino viable para la espintrónica de semiconductores de alta temperatura y las tecnologías de conmutación magnética.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
- Física de los semiconductores Física de los semiconductores
Sus antecedentes:
- El efecto del campo eléctrico en semiconductores ferromagnéticos es crucial para las aplicaciones espintrónicas, permitiendo la conmutación de la magnetización.
- Lograr el ferromagnetismo a temperatura ambiente en semiconductores es un desafío significativo para la espintrónica práctica.
Objetivo del estudio:
- Para demostrar el ferromagnetismo inducido por el campo eléctrico a temperatura ambiente en un semiconductor de óxido magnético.
- Para investigar el papel de los portadores de electrones en el ferromagnetismo de alta temperatura.
- Para establecer una ruta hacia la espintrónica de semiconductores a temperatura ambiente.
Principales métodos:
- Se utilizó un cerramiento eléctrico de doble capa en un semiconductor de óxido magnético (Ti,Co) O ((2).
- Se logró una acumulación de electrones de alta densidad superior a 10^14 cm^-2.
- Aplica voltajes de puerta de unos pocos voltios para modular el estado magnético del material.
Principales resultados:
- Se ha demostrado el ferromagnetismo inducido por el campo eléctrico a temperatura ambiente.
- Transformó un estado paramagnético de baja carga en un estado ferromagnético de alta carga.
- Mostró el papel significativo de los portadores de electrones en la habilitación del ferromagnetismo a alta temperatura.
Conclusiones:
- El ferromagnetismo inducido por el campo eléctrico es alcanzable a temperatura ambiente en (Ti,Co) O(2).
- Los portadores de electrones juegan un papel crítico en el ferromagnetismo de alta temperatura.
- Este trabajo presenta un enfoque prometedor para la espintrónica de semiconductores a temperatura ambiente.
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