Near-field imaging of dipole emission modulated by an optical grating

Dong Hyuk Ko; Graham G. Brown; Chunmei Zhang; P. B. Corkum

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arXiv · 2010.05017

Near-field imaging of dipole emission modulated by an optical grating

Dong Hyuk Ko·Graham G. Brown·Chunmei Zhang·P. B. Corkum

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Abstract

Multiphoton-ionized electrons are born into a strong light field that will determine their short-term future. By controlling the infrared beam, we enable atoms or molecules to generate extreme ultraviolet (XUV) pulses and synthesize attosecond pulses - the shortest controlled events ever produced. Here we show that a weak obliquely incident beam imposes an optical grating on the fundamental beam, resulting in a spatially modulated attosecond pulse. We observe the modulation on a spectrally resolved near-field XUV image, encoding all information of the spectral phase of the recollision electron and, therefore, the attosecond pulse produced by structureless atoms. Near-field imaging is an efficient method for measuring the duration of attosecond pulses, especially important for soft X-ray pulses created in helium. For more complex systems, it includes auto ionization and giant plasmon resonances.

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Dong Hyuk Ko, Graham G. Brown, Chunmei Zhang, P. B. Corkum. 2020-10-10. Near-field imaging of dipole emission modulated by an optical grating. https://arxiv.org/abs/2010.05017

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