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Tunelado dependiente del espín en superredes de cobalto-nanocristal autoensambladas
C T Black1, C B Murray, R L Sandstrom
1IBM Research Division, T. J. Watson Research Center, Yorktown Heights, NY 10598, USA. ctblack@us.ibm.com
Science (New York, N.Y.)
|November 10, 2000
Resumen
Las matrices de nanocristales de cobalto muestran un transporte de electrones dependiente del espín. Su magnetorresistencia alcanza el 10% a bajas temperaturas, limitada por la dispersión spin-flip a temperaturas más altas.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada Física de la materia condensada Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Las nanoestructuras autoensambladas ofrecen propiedades electrónicas únicas.
- Los nanocristales de cobalto son prometedores para las aplicaciones espintrónicas.
Objetivo del estudio:
- Para investigar el transporte de electrones dependientes del espín en matrices de nanocristales de cobalto.
- Para caracterizar las propiedades de magnetorresistencia de estos dispositivos.
Principales métodos:
- Fabricación de matrices periódicas de nanocristales de cobalto de 10 nm.
- Medición de las características de corriente-tensión.
- Análisis de la magnetorresistencia a bajas temperaturas (por debajo de 20 K).
Principales resultados:
- Los dispositivos exhiben un transporte de electrones dependiente del espín.
- Los datos de corriente-voltaje se alinean con los modelos de túnel de un solo electrón.
- Las relaciones de magnetorresistencia se acercan al 10% a bajas temperaturas.
- Se identificó la dispersión de Spin-Flip como un factor clave que afecta la magnetorresistencia.
Conclusiones:
- Las matrices autoensambladas de nanocristales de cobalto son viables para dispositivos espintrónicos.
- Comprender los mecanismos de transporte y la dispersión es crucial para optimizar el rendimiento.
- El rendimiento del dispositivo es dependiente de la temperatura y la tensión de sesgo.
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