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Intercambio fonónico de la magnetización por el efecto Barnett ultrarrápido
C S Davies1,2, F G N Fennema3,4, A Tsukamoto5
1FELIX Laboratory, Radboud University, Nijmegen, The Netherlands. carl.davies@ru.nl.
Nature
|April 10, 2024
Resumen
El efecto Barnett ultra rápido utiliza el giro para inducir la magnetización. Este estudio muestra que puede revertir no localmente los estados magnéticos utilizando fonones excitados por láser, ofreciendo un control magnético selectivo ultrarrápido.
Área de la Ciencia:
- La física
- Ciencias de los materiales
- El magnetismo
Sus antecedentes:
- El efecto Barnett describe la magnetización del giro mecánico.
- Los pulsos láser ultrarrápidos pueden desmagnetizar los ferromagnetos a través del efecto Einstein-de Haas.
- El uso de vibraciones de celosía para cambiar estados magnéticos cercanos sigue siendo inexplorado.
Objetivo del estudio:
- Para investigar el cambio recíproco de la magnetización utilizando el efecto Barnett ultrarrápido.
- Para explorar el control magnético no local a través de fonones inducidos por láser.
Principales métodos:
- Excitación por resonancia de fonones ópticos polarizados circularmente en un sustrato paramagnético.
- Utilizando el efecto Barnett ultrarrápido para inducir una magnetización temporal.
- Demostrando la inversión del estado magnético en una heterostructura adyacente.
Principales resultados:
- La magnetización espontánea se obtuvo temporalmente a través del efecto Barnett ultrarrápido.
- Esta magnetización inducida invirtió permanentemente el estado magnético de una heterostructura.
- La dirección de la conmutación magnética estaba controlada por la mano del fonón.
Conclusiones:
- El efecto Barnett ultrarrápido se puede utilizar para la conmutación magnética no local.
- Este método ofrece un control selectivo y potencialmente universal ultrarrápido del orden magnético.
- La conmutación magnética impulsada por fonones representa un nuevo enfoque en la espintrónica.
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