Gouy phase effects in attosecond photoemission delay measurements using truncated beams

Autor: Lukas Gallmann, Lamia Kasmi, Matteo Lucchini, Mikhail Volkov, Fabian Schlaepfer, Ursula Keller, André Ludwig
Rok vydání: 2017
Předmět:
Zdroj: Scopus-Elsevier
DOI: 10.1109/cleoe-eqec.2017.8086774
Popis: In attosecond metrology, an attosecond extreme-ultraviolet (XUV) pulse is combined with a phase-locked few-cycle infrared (IR) pulse to study ultrafast electron dynamics on the sub-to few-femtosecond time scale. Due to the strong absorption of materials in the XUV regime, the beam recombination is commonly done geometrically, for example with a center-hole mirror (Fig. 1 (a)). In this case, the XUV beam is transmitted through the hole in the center. The larger IR beam is reflected on the outer part of the mirror. This results in an annular beam profile with propagation parameters deviating considerably from those of an ideal Gaussian, which also affects the Gouy phase behavior across the focus [1, 2]. Here, we present a detailed study of the Gouy phase of a truncated beam using our two-foci setup (Fig. 1 (a)) in combination with the RABBITT [3] (Reconstruction of Attosecond Beating By Interference of Two-photon Transitions) technique. Furthermore, we discuss the non-negligible influence of the Gouy phase shift on attosecond pump-probe measurements with spatially separated targets.
Databáze: OpenAIRE