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Updated: Jun 12, 2026
06:08
Time-resolved Photophysical Characterization of Triplet-harvesting Organic Compounds at an Oxygen-free Environment Using an iCCD Camera
Published on: December 27, 2018
Retraso en la fotoemisión
M Schultze1, M Fiess, N Karpowicz
1Department für Physik, Ludwig-Maximilians-Universität, Am Coulombwall 1, D-85748 Garching, Germany. Martin.Schultze@mpq.mpg.de
Science (New York, N.Y.)
|June 26, 2010
Resumen
Los científicos midieron un retraso de 21 attosegundos en la emisión de electrones de los átomos de neón utilizando la metrología attosegundo. Este hallazgo desafía las suposiciones de fotoemisión instantánea y refina el cronometraje a escala atómica para la dinámica de los electrones.
Área de la Ciencia:
- Física atómica es la física atómica.
- La mecánica cuántica es la mecánica cuántica.
- Ciencia ultrarrápida Ciencia ultrarrápida.
Sus antecedentes:
- Tradicionalmente se supone que la fotoemisión es instantánea.
- Esta suposición sustenta la definición de tiempo cero para el seguimiento del movimiento de electrones a escala atómica.
Objetivo del estudio:
- Para investigar el momento de la fotoemisión de diferentes orbitales atómicos.
- Explorar el potencial de la metrología del attosegundo para la medición precisa del tiempo a escala atómica.
Principales métodos:
- Utilizó la metrología attosegundo para sondear la emisión de electrones de los átomos de neón.
- Empleó un pulso de luz de 100 electrones-voltios para ionizar el neón.
Principales resultados:
- Se observó un retraso significativo de 21 ± 5 attosegundos en la fotoemisión de electrones de los orbitales 2p del neón en comparación con sus orbitales 2s.
- Se demostró que el tiempo de fotoemisión varía entre diferentes estados cuánticos.
Conclusiones:
- El estudio revela un retraso medible en la fotoemisión, desafiando el modelo de emisión instantánea.
- La metrología de cronometraje de un segundo ofrece un método preciso para sondear la dinámica de muchos electrones y refinar la cronoscopia atómica.
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