Video Experimental Relacionado
Updated: Oct 13, 2025

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Observación experimental del orden magnético de largo alcance en cuasicristales icosaédricos
Ryuji Tamura1, Asuka Ishikawa2, Shintaro Suzuki1
1Department of Materials Science and Technology, Tokyo University of Science, Katsushika, Tokyo 125-8585, Japan.
Los investigadores descubrieron el orden magnético de largo alcance en cuasicristales icosaédricos (i QC) hechos de oro, galio y gadolinio o terbium. Este hallazgo desafía las suposiciones anteriores sobre los cuasicristales que carecen de ordenamiento magnético.
Área de la Ciencia:
- Ciencias de los materiales
- Física de la materia condensada
- El magnetismo
Sus antecedentes:
- Los cuasicristales (QC) suelen carecer de orden magnético de largo alcance.
- Estudios previos sobre cuasicristales magnéticos reportaron comportamientos similares a los de un vidrio giratorio.
Objetivo del estudio:
- Investigar la posibilidad de un orden magnético de largo alcance en cuasicristales icosaédricos reales.
- Para sintetizar y caracterizar los compuestos magnéticos cuasicristalinos Au-Ga-Gd y Au-Ga-Tb.
Principales métodos:
- Síntesis de Au-Ga-Gd y Au-Ga-Tb icosahedral de los cristales.
- Mediciones de la sensibilidad magnética y del calor específico.
- Experimentos de difracción de neutrones.
Principales resultados:
- Au65Ga20Gd15 i QC muestra una transición ferromagnética a 23 K con picos magnéticos de Bragg.
- Au65Ga20Tb15 i QC también exhibe un comportamiento ferromagnético a 16 K, confirmado por difracción de neutrones.
- Esta es la primera observación de orden magnético de largo alcance en un cuasicristal real.
Conclusiones:
- Los cuasicristales icosaédricos reales pueden exhibir un orden ferromagnético de largo alcance.
- Estos hallazgos abren nuevas vías para el estudio de fenómenos magnéticos exóticos en sistemas cuasiperiódicos.
- El estudio pone de relieve el potencial de los cuasicristales con simetría icosaédrica para nuevas aplicaciones magnéticas.
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