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Fotoionización de las moléculas quirales con resolución de atotsegundo
S Beaulieu1,2, A Comby3, A Clergerie3
1Université de Bordeaux, CNRS, Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA), Centre Lasers Intenses et Applications (CELIA), UMR5107, F33405 Talence, France. beaulieus@emt.inrs.ca.
Science (New York, N.Y.)
|December 9, 2017
Resumen
Los investigadores midieron un retraso de 24 attosegundos entre las emisiones de electrones hacia adelante y hacia atrás durante la fotoionización quiral de la alcanfora. Esta interferometría de fotoelectrones en el segundo revela fuertes señales quirales de la dinámica electrónica.
Área de la Ciencia:
- La óptica cuántica
- Un segundo de ciencia
- Espectroscopia quiróptica
Sus antecedentes:
- Las interacciones quirales luz-materia son cruciales para la discriminación de los enantiómeros.
- La fotoionización ofrece señales quirales más fuertes que las respuestas de electrones unidos.
- Las asimetrías en la distribución angular de los fotoelectrones revelan información quiral.
Objetivo del estudio:
- Para medir el perfil temporal de paquetes de ondas de electrones en la fotoionización quiral.
- Para investigar la dinámica temporal de los fotoelectrones expulsados del alcanfor.
- Para revelar el carácter quiral en una dinámica electrónica fuertemente correlacionada.
Principales métodos:
- Implementación de la interferometría de fotoelectrones auto-referenciada por segundo.
- Usó pulsos de láser circularmente polarizados para ionizar moléculas de alcanfor.
- Retrasos de tiempo medidos entre la emisión de paquetes de ondas de electrones hacia adelante y hacia atrás.
Principales resultados:
- Se midió un retraso temporal de hasta 24 attosegundos entre los electrones expulsados hacia adelante y hacia atrás.
- Se encontró que el retraso dependía del ángulo de eyección de electrones.
- Se observaron formas temporales asimétricas de paquetes de ondas de electrones desde estados de autoionización.
Conclusiones:
- La interferometría de attosegundos proporciona información sobre la dinámica electrónica quiral.
- La dinámica de la fotoionización revela los aspectos temporales de la quiralidad molecular.
- Las dinámicas electrónicas fuertemente correlacionadas exhiben un carácter quiral distinto.
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