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Clases de universalidad para el movimiento de la pared de dominio en el semiconductor ferromagnético (Ga,Mn) As.
M Yamanouchi1, J Ieda, F Matsukura
1Semiconductor Spintronics Project, Exploratory Research for Advanced Technology, Japan Science and Technology Agency, 1-18 Kitamemachi, Aoba-ku, Sendai 980-0023, Japan.
Science (New York, N.Y.)
|September 22, 2007
Resumen
Este estudio revela mecanismos distintos que impulsan el movimiento de la pared del dominio magnético en semiconductores ferromagnéticos. Los campos magnéticos y las corrientes de espín exhiben diferentes leyes de escala, lo que indica una física subyacente fundamentalmente diferente.
Área de la Ciencia:
- Spintronics es una empresa de Spintronics.
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- El movimiento de la pared del dominio magnético es crucial para los dispositivos espintrónicos.
- La comprensión de los mecanismos de conducción por los campos magnéticos y las corrientes de giro es esencial pero incompleta.
- Los semiconductores ferromagnéticos como (Ga,Mn) As ofrecen una plataforma única para estudiar estos fenómenos.
Objetivo del estudio:
- Para comparar experimentalmente los mecanismos de movimiento de las paredes del dominio magnético inducidos por campos magnéticos y corrientes polarizadas por espín.
- Para investigar el régimen de arrastre activado térmicamente en (Ga,Mn) As.As.
- Para aclarar las diferencias fundamentales en los mecanismos de accionamiento.
Principales métodos:
- Medidas experimentales de la velocidad de la pared del dominio en (Ga,Mn) As.As.
- Análisis del movimiento en el régimen de fluencia regido por una ley de escala de Arrhenius.
- Comparación de exponentes de la ley de escala para el movimiento impulsado por el campo y el movimiento impulsado por la corriente.
Principales resultados:
- Velocidad de la pared del dominio en (Ga,Mn) Siguiendo una ley de escala de Arrhenius en el régimen de arrastre.
- Los exponentes para el movimiento impulsado por corriente y el movimiento impulsado por campo son significativamente diferentes.
- Estas diferencias indican distintas clases de universalidad para los dos mecanismos de accionamiento.
Conclusiones:
- Los mecanismos fundamentales que impulsan el movimiento de la pared del dominio magnético por los campos magnéticos y las corrientes de espín son fundamentalmente diferentes.
- Las diferencias observadas en las leyes de escala proporcionan información crítica sobre la física de la dinámica de las paredes de dominio en semiconductores ferromagnéticos.
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