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Control ultrarrápido no térmico de la magnetización mediante pulsos fotomagnéticos instantáneos
A V Kimel1, A Kirilyuk, P A Usachev
1IMM, Radboud University Nijmegen, 6525 ED Nijmegen, The Netherlands.
Nature
|May 27, 2005
Resumen
Los láseres ultrarrápidos ahora pueden controlar el magnetismo de manera no térmica utilizando pulsos polarizados circularmente a través del efecto Faraday inverso. Esta interacción fotomagnética ofrece un control de giro más rápido y eficiente para dispositivos magnéticos avanzados.
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
- Las ópticas ultrarrápidas son ópticas ultrarrápidas.
- Spintronics es una empresa de Spintronics.
Sus antecedentes:
- La creciente demanda de almacenamiento de datos de alta densidad y manipulación rápida impulsa la investigación más allá del control del campo magnético.
- La actual manipulación magnética basada en láser se basa en efectos térmicos, limitando la velocidad debido a los requisitos de tiempo de enfriamiento.
Objetivo del estudio:
- Para demostrar un mecanismo no térmico para el control de giro magnético ultrarrápido utilizando pulsos láser.
- Para explorar el efecto inverso de Faraday para la manipulación de la dinámica de espín coherente.
Principales métodos:
- Utilizando pulsos láser de femtosegundos polarizados circularmente.
- Investigando el efecto inverso de Faraday para las interacciones fotomagnéticas.
Principales resultados:
- Se logra una excitación no térmica y un control coherente de la dinámica de espín.
- Se demostró una interacción fotomagnética instantánea limitada solo por el ancho del pulso láser (aprox. 200 pies cuadrados).
Conclusiones:
- Estableció un nuevo mecanismo para el control de espín coherente ultrarrápido.
- Abrió nuevas vías para aplicaciones láser ultrarrápidas en dispositivos magnéticos, superando las limitaciones térmicas.
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