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arXiv · 0801.1194

Non-perturbative QED Model with Dressed States to Tackle HHG in Ultrashort Intense Laser Pulses

Huayu Hu·Jianmin Yuan
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Abstract

A generalization of non-perturbative QED model for high harmonic generation is developed for the multi-mode optical field case. By introducing classical-field-dressed quantized Volkov states analytically, a formula to calculate HHG for hydrogen-like atom in ultrashort intense laser pulse is obtained, which has a simple intuitive interpretation. The dressed state QED model indicates a new perspective to understand HHG, for example, the presence of the weak even-order harmonic photons, which has been verified by both theoretical analysis and numerical computation. Long wavelength approximation and strong field approximation are involved in the development of the formalism.

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Huayu Hu, Jianmin Yuan. 2008-01-08. Non-perturbative QED Model with Dressed States to Tackle HHG in Ultrashort Intense Laser Pulses. https://doi.org/10.1103/physreva.78.063826

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