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[60]Las películas de poliuretano que contienen fullereno con una gran no-resonancia ultrarrápida no lineal de tercer
Li Kuang1, Qiying Chen, Edward H Sargent
1Department of Chemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6.
Journal of the American Chemical Society
|November 6, 2003
Resumen
Los investigadores desarrollaron películas de poliuretano C60 entrelazadas que exhiben una no linealidad óptica de tercer orden ultrarrápida mejorada. Estos materiales muestran mejoras significativas sobre el C60 prístino y otros derivados para aplicaciones ópticas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La óptica es la óptica.
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
Sus antecedentes:
- Los fullerenos, particularmente el C60, son conocidos por sus propiedades ópticas no lineales.
- El desarrollo de materiales avanzados con una mayor no linealidad óptica es crucial para las aplicaciones fotónicas.
- Los derivados anteriores del C60 y los polímeros conjugados mostraron respuestas ópticas no lineales prometedoras pero limitadas.
Objetivo del estudio:
- Demostrar y caracterizar la no linealidad óptica ultrarrápida de tercer orden en nuevas películas de poliuretano reticuladas que contienen C60.
- Investigar la mejora de la no linealidad óptica en comparación con el C60 prístino y otros materiales relacionados.
- Explorar el potencial de estas películas para aplicaciones en dispositivos ópticos que funcionan a longitudes de onda específicas.
Principales métodos:
- Fabricación de películas de poliuretano que contienen C60 mediante el enlace cruzado de un derivado de C60 que contiene hidroxilo y un triisocianato.
- Utilizando la técnica Z-scan para medir y cuantificar la no linealidad óptica de tercer orden.
- Caracterizando el índice de refracción no lineal (n2), la susceptibilidad no lineal de tercer orden (chi) y la absorción no lineal (gamma).
Principales resultados:
- Se logró una no linealidad óptica de tercer orden significativamente mejorada y ultrarrápida a longitudes de onda de 1150-1600 nm.
- Se obtienen películas de polímero de buena calidad con una alta carga de derivados C60.
- Se midió un coeficiente de Kerr positivo con un índice de refracción no lineal (n2) en el rango de (3.7 ± 0.80) x 10^-4 a (2.0 ± 0.6) x 10^-3 cm2/GW.
- Calculado los valores de chi ((3) y gamma hasta 9.7 x 10^-11 y 9.6 x 10^-32 esu a 1550 nm.
- Demostró varios órdenes de mejora sobre el C60 prístino y 1-2 órdenes sobre los derivados recientes del C60 y los polímeros conjugados.
Conclusiones:
- Las películas de poliuretano C60 reticuladas exhiben una no linealidad óptica de tercer orden ultrarrápida superior.
- Estos materiales ofrecen un avance significativo para la óptica no lineal, superando a los materiales existentes basados en C60.
- Las películas desarrolladas son prometedoras para aplicaciones fotónicas y optoelectrónicas avanzadas que requieren un alto rendimiento óptico no lineal.
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