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Updated: Jul 11, 2025
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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Grandes campos magnéticos efectivos de fonones quirales en haluros de tierras raras
Jiaming Luo1,2, Tong Lin1, Junjie Zhang1
1Department of Materials Science and Nano Engineering, Rice University, Houston, TX 77005, USA.
Science (New York, N.Y.)
|November 9, 2023
Resumen
Los fonones quirales coherentes, impulsados por la luz, pueden magnetizar materiales transitoriamente como un fuerte campo magnético. Este acoplamiento de espín-fonón ofrece nuevas vías para el magnetismo ultrarrápido y la espíntrónica.
Área de la Ciencia:
- Física de la materia condensada
- Ciencias de los materiales
- La óptica cuántica
Sus antecedentes:
- La simetría de reversión del tiempo (TRS) es fundamental para muchas propiedades de los materiales.
- Los fonones quirales rompen el TRS creando estructuras dinámicas de celosía a través del movimiento atómico unidireccional.
Objetivo del estudio:
- Investigar la influencia de los fonones quirales coherentes en la polarización del espín paramagnético.
- Para explorar el potencial de acoplamiento de espín-fonón impulsado por luz para el control magnético.
Principales métodos:
- Excitación de fonones quirales utilizando pulsos de luz de terahertz polarizados circularmente.
- Las mediciones de la rotación de Faraday y la elipticidad de Kerr con resolución temporal para detectar la magnetización transitoria.
- Desarrollo y aplicación de un modelo de acoplamiento de espín-fonón.
Principales resultados:
- La luz polarizada circularmente resonante con fonones indujo una magnetización transitoria en el fluoruro de cerio.
- La magnetización inducida imitó un campo magnético de ~ 1 tesla.
- La magnetización fue proporcional al momento angular del fonón y la susceptibilidad magnética a bajas temperaturas.
Conclusiones:
- Los fonones quirales coherentes pueden polarizar eficazmente los espines, actuando como un campo magnético transitorio.
- Esta interacción de espín-fonón proporciona una nueva vía para la investigación del magnetismo ultrarrápido.
- Las aplicaciones potenciales incluyen la espintrónica energéticamente eficiente y el estudio de las fases de no equilibrio con TRS roto.
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