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Dinámicas asimétricas de giro y desmagnetización impulsadas por campos láser en altermagnetos bidimensionales
Shuo Li1, Ran Wang1, Thomas Frauenheim1,2
1Institute for Advanced Study, Chengdu University, Chengdu 610106, China.
Nano letters
|February 9, 2026
Resumen
Los investigadores exploraron las dinámicas de magnetización ultrarrápida en altermagnetos 2D (AM). Los pulsos láser indujeron una desmagnetización asimétrica en Fe2WTe4, creando un estado ferrimagnético fotoinducido sintonizable por polarización láser.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
- Fenómenos ultrarrápidos son fenómenos ultrarrápidos.
Sus antecedentes:
- Las dinámicas de magnetización ultrarrápida se entienden en los imanes convencionales.
- Los altermagnetos (AM) presentan una nueva frontera para explorar las interacciones de la materia ligera.
- El comportamiento de los AM semiconductores 2D bajo excitación láser es en gran parte desconocido.
Objetivo del estudio:
- Investigar las dinámicas de magnetización ultrarrápida inducida por láser en altermagnetos 2D.
- Explorar el potencial para el control de magnetismo impulsado por la luz en estos materiales.
- Descubra los mecanismos microscópicos detrás de la dinámica de espín inducida por láser en Fe2WTe4.
Principales métodos:
- Empleó la teoría funcional de densidad dependiente del tiempo en tiempo real (rt-TDDFT).
- Simuló la interacción de pulsos láser con un altermagnético semiconductor 2D (Fe2WTe4).
- Se analizaron las dinámicas de desmagnetización y espín resueltas en la subrejilla.
Principales resultados:
- Demostración de la desmagnetización asimétrica entre las subaltas de Fe en Fe2WTe4.
- Logró un estado ferrimagnético fotoinducido con una magnetización neta de ~0.3 μB por unidad celular.
- Se observaron dinámicas de espín sintonizables y no collineares y inclinación de espín controlada por polarización láser.
Conclusiones:
- Los pulsos láser pueden inducir dinámicas únicas de magnetización ultrarrápida en 2D AMs.
- La división de espín dependiente del momento y el efecto óptico de transferencia de espín entre sitios (OISTR) impulsan estas dinámicas.
- La luz ofrece una vía para controlar las texturas de giro y lograr nuevos estados magnéticos en 2D AMs.
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