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El control de los dieléctricos con el campo eléctrico de la luz
Martin Schultze1, Elisabeth M Bothschafter, Annkatrin Sommer
1Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany. martin.schultze@mpq.mpg.de
Nature
|December 11, 2012
Resumen
Los científicos demostraron el control reversible de las propiedades dieléctricas utilizando campos de luz intensos. Este avance permite la manipulación ultrarrápida de señales ópticas, allanando el camino para la electrónica y las comunicaciones con ancho de banda de petahertz.
Área de la Ciencia:
- Física del estado sólido física del estado sólido.
- La óptica cuántica es una óptica cuántica.
- Ciencia de los materiales ciencia de los materiales.
Sus antecedentes:
- El control del campo de microondas de las propiedades de los semiconductores es fundamental para la electrónica.
- Extender el control eléctrico a frecuencias ópticas requiere materiales de banda ancha como los dieléctricos.
- Se necesitan fuertes campos eléctricos para alterar las propiedades dieléctricas, con pulsos láser de pocos ciclos que permiten una modificación sin daños.
Objetivo del estudio:
- Investigar la viabilidad de manipular reversiblemente la estructura electrónica y la polarizabilidad eléctrica de los dieléctricos utilizando el campo eléctrico de la luz.
- Explorar el potencial para el procesamiento de señales ultrarrápidas en frecuencias ópticas.
Principales métodos:
- Se empleó espectroscopia de estado sólido de subfemtosegundos para estudiar la dinámica de los electrones.
- La sílice fundida fue irradiada con pulsos láser de pocos ciclos de infrarrojo cercano controlados por la forma de onda (varios voltios por angström).
- Los cambios en la absortividad ultravioleta extrema y la reflectividad del infrarrojo cercano se probaron en escalas de tiempo de attosegundo a femtosegundo.
Principales resultados:
- Se observó que los cambios inducidos por el campo en las propiedades dieléctricas seguían el comportamiento del campo de luz principal de una manera altamente no lineal.
- Los efectos demostraron una reversibilidad ultrarrápida, que ocurre en escalas de tiempo de aproximadamente cien attosegundos a unos pocos femtosegundos.
- Los resultados se alinean con las predicciones de un modelo mecánico cuántico.
Conclusiones:
- El campo eléctrico de la luz puede controlar reversiblemente las propiedades físicas de los dieléctricos.
- Esto ofrece potencial para la manipulación de señales en anchos de banda de petahertz.
- Los hallazgos abren nuevas vías para las comunicaciones ópticas y el procesamiento de información.
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