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Transporte mejorado por el desorden en cuasicristales fotónicos
Liad Levi1, Mikael Rechtsman, Barak Freedman
1Department of Physics and Solid State Institute, Technion, Haifa, Israel.
Science (New York, N.Y.)
|May 14, 2011
Resumen
El desorden puede mejorar el transporte de ondas en los cuasicristales, lo que lleva a la expansión del haz y al transporte difusivo antes de la localización de Anderson. Esto desafía la comprensión convencional de los efectos del trastorno en la propagación de las ondas.
Área de la Ciencia:
- Física de la materia condensada Física de la materia condensada
- Ciencia de los materiales Ciencia de los materiales.
- Fenómenos de ondas son fenómenos de ondas.
Sus antecedentes:
- Los cuasicristales exhiben estructuras aperiódicas únicas con simetrías rotacionales prohibidas.
- El trastorno suele suprimir el transporte de ondas en medios periódicos y aperiódicos.
- Comprender el transporte de ondas en estructuras complejas es crucial para el diseño de materiales.
Objetivo del estudio:
- Observar y caracterizar experimentalmente el efecto del desorden en el transporte de ondas en cuasicristales.
- Para investigar la transición del transporte mejorado por el desorden a la localización de Anderson.
- Para aclarar los orígenes fundamentales de estos fenómenos en medios casi cristalinos.
Principales métodos:
- Experimentos llevados a cabo utilizando cuasicristales fotónicos.
- Variación sistemática de los niveles de trastorno en el medio cuasicristalino.
- Mediciones de propagación del haz óptico para analizar las características del transporte.
Principales resultados:
- Se observó un transporte de ondas mejorado por el desorden, lo que lleva a una mayor expansión del haz.
- Identificó un régimen de transporte de tipo difusivo con creciente desorden.
- Demostró una transición a la localización de Anderson y suprimió el transporte en niveles de desorden más altos.
Conclusiones:
- El desorden puede mejorar inesperadamente el transporte de ondas en los cuasicristales, contrariamente a las expectativas convencionales.
- El estudio revela una compleja interacción entre el desorden y la estructura cuasicristalina que afecta la propagación de las ondas.
- Los hallazgos proporcionan nuevos conocimientos sobre la dinámica de ondas en sistemas aperiódicos desordenados.
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