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arXiv · 1601.05923

Bright high-order harmonic generation with controllable polarization from a relativistic plasma mirror

Zi-Yu Chen·Alexander Pukhov
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Abstract

Ultrafast extreme ultraviolet (XUV) sources with a controllable polarization state are powerful tools for investigating the structural and electronic as well as the magnetic properties of materials. However, such light sources are still limited to only a few free-electron laser facilities and, very recently, to high-order harmonic generation from noble gases. Here we propose and numerically demonstrate a laser-plasma scheme to generate bright XUV pulses with fully controlled polarization. In this scheme, an elliptically-polarized laser pulse is obliquely incident on a plasma surface, and the reflected radiation contains pulse trains and isolated circularly- or highly-elliptically-polarized attosecond XUV pulses. The harmonic polarization state is fully controlled by the laser-plasma parameters. The mechanism can be explained within the relativistically oscillating mirror model. This scheme opens a practical and promising route to generate bright attosecond XUV pulses with desirable ellipticities in a straightforward and efficient way for a number of applications.

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Zi-Yu Chen, Alexander Pukhov. 2016-01-22. Bright high-order harmonic generation with controllable polarization from a relativistic plasma mirror. https://doi.org/10.1038/ncomms12515

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