Spatial and temporal metrology of coherent ultrashort pulses inthe extreme-ultraviolet domain

Abstract : Ultrashort pulses of extreme-ultraviolet (XUV) radiation have a wide range of applications in fields such as plasma probing, spectroscopy, or the study of ultrafast dynamics in atoms and molecules.Nowadays, there are three main sources of such pulses. High-order harmonic generation (HHG) in rare gases or solid surfaces is able to provide attosecond pulses. However, their limited energy, of the order of nanojoules, limits its number of applications. The amplification of high-harmonic pulses in laser-driven plasmas (SXRL) has been demonstrated to provide energies of tens of microjules. Higher pulse energies can be obtained from seeded XUV free-electron lasers (FELs), large-scale facilities with more limited accessibility.In recent years, significant progress has been made with each of these sources towards the generation of shorter pulses. It is thus necessary to develop new techniques for full temporal metrology of ultrashort XUV pulses. Additionally, many experiments, such as those involving nonlinear phenomena, require high XUV intensities. Efficient focusing of low-energy pulses can significantly increase their range of application. Good wavefronts are required in order to focus XUV pulses to high intensities, and the optics must be of high quality and precisely aligned.In this thesis, the spatial properties of high-harmonic pulses are extensively explored thanks to the use of an XUV Hartmann wavefront sensor. This device is also proven here to be useful for tabletop, at-wavelength characterization and optimization of XUV optical systems with HHG sources.The problem of performing full temporal characterization of XUV pulses is also discussed in detail, and two new schemes for complete pulse reconstruction for seeded XUV FELs and seeded SXRLs are presented. Finally, the first implementation of chirped pulse amplification (CPA) in a seeded XUV FEL is reported, and its implementation in seeded SXRLs is discussed as well.
Document type :
Liste complète des métadonnées
Contributor : Abes Star <>
Submitted on : Wednesday, December 20, 2017 - 10:23:27 AM
Last modification on : Thursday, April 11, 2019 - 7:20:36 AM


Version validated by the jury (STAR)


  • HAL Id : tel-01668564, version 1


Hugo Dacasa Pereira. Spatial and temporal metrology of coherent ultrashort pulses inthe extreme-ultraviolet domain. Optics [physics.optics]. Université Paris-Saclay, 2017. English. ⟨NNT : 2017SACLX041⟩. ⟨tel-01668564⟩



Record views


Files downloads