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arXiv · 1710.05727

Micro-focusing of broadband high-order harmonic radiation by a double toroidal mirror

Hélène Coudert-Alteirac·Hugo Dacasa·Filippo Campi·Emma Kueny·Balázs Farkas·Fabian Brunner·Sylvain Maclot·Bastian Manschwetus·Hampus Wikmark·Jan Lahl·Linnea Rading·Jasper Peschel·Balázs Major·Katalin Varjú·Guillaume Dovillaire·Philippe Zeitoun·Per Johnsson·Anne L'Huillier·Piotr Rudawski
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Abstract

We present an optical system based on two toroidal mirrors in a Wolter configuration to focus broadband XUV radiation. Optimization of the focusing optics alignment is carried out with the aid of an XUV wavefront sensor. Back-propagation of the optimized wavefront to the focus yields a focal spot of 3.6$\times$4.0 $\mu$m$^2$ full width at half maximum, which is consistent with ray-tracing simulations that predict a minimum size of 3.0$\times$3.2 $\mu$m$^2$. This work is important for optimizing the intensity of focused high-order harmonics in order to reach the nonlinear interaction regime.

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Hélène Coudert-Alteirac, Hugo Dacasa, Filippo Campi, Emma Kueny, Balázs Farkas, Fabian Brunner, Sylvain Maclot, Bastian Manschwetus, Hampus Wikmark, Jan Lahl, Linnea Rading, Jasper Peschel, Balázs Major, Katalin Varjú, Guillaume Dovillaire, Philippe Zeitoun, Per Johnsson, Anne L'Huillier, Piotr Rudawski. 2017-10-11. Micro-focusing of broadband high-order harmonic radiation by a double toroidal mirror. https://doi.org/10.3390/app7111159

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