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

Hélène Coudert-Alteirac , Hugo Dacasa (1) , 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 (1) , Per Johnsson , Anne L'Huillier , Piotr Rudawski

1 LOA - Laboratoire d'optique appliquée

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.

Domaines: Instrumentations et Détecteurs [physics.ins-det]; Physique Générale [physics.gen-ph]

Hélène Coudert-Alteirac, Hugo Dacasa, Filippo Campi, Emma Kueny, Balázs Farkas, et al.. Micro-focusing of broadband high-order harmonic radiation by a double toroidal mirror. Appl.Sciences, 2017, 7 (11), pp.1159. ⟨10.3390/app7111159⟩. ⟨hal-01669428⟩