Design and characterization of the XUV monochromator for ultrashort pulses at the ARTEMIS facility

Abstract

ARTEMIS, a multi-partner and multidisciplinary project, will be a users-dedicated facility that will provide ultrashort XUV pulses through high harmonic generation in a gas target. This high repetition rate synchronized source will allow new science in research fields spanning from the material science to the molecular physics and chemistry. The XUV radiation is expected to cover the range 10 -100 nm with an estimated photons flux up to 10 11 photons/s per harmonic. In this work we present the design and characterization of the monochromator that will be used in the beamline for the experiments requiring wavelength and bandwidth selection. The working principle is based on a plane grating operated at grazing incidence in the off-plane mount. This geometry has been selected because of the high diffraction efficiency, expected to be about 30%. To cover the entire spectral range four gratings can be selected which span over different regions and with different spectral resolution. When the appropriate grating is chosen, the wavelength scanning is performed by rotating the grating around an axis passing through the grating center and parallel to the grooves direction. The off-plane mount requires the grating to be used in collimated light, consequently the optical scheme is completed by two toroidal mirrors, the first in front of the source that collimates the XUV radiation before the grating and the second after the grating to focalize the spectrally dispersed photons on the exit slit. Using a single grating, the configuration is not time-delay-compensated, nevertheless the time broadening (depending on the source divergence, the wavelength, and the grating) is less than 50 fs.

Ultrafast science and development at the Artemis facility

“…The diffracted light is refocused by a second toroidal mirror on to the exit slit of the monochromator, as shown in Figure 6. The grating is used in conical illumination (with the direction of light propagation nearly parallel to the plane of the rulings) to limit the time spread of the pulses and maintain the required resolving power and high efficiency 10,11,12 .…”

Life funds, urban development, and the experimental practices of financial sociology

“…This point is made incisively in Christophers ' (2015) analysis of the 'mushrooming' literature on financialization as the (then) latest 'ization' -after neoliberalization and globalization summoned to define the political economies of contemporary capitalism. 6 Two of Christophers' complaints about the '17 going on 27 meanings of financialization' (182) are vital. The first is historical.…”

A high-order harmonic generation apparatus for time- and angle-resolved photoelectron spectroscopy

“…Both approaches can be modified to make use of conical diffraction to achieve higher transmission. 21,35 An alternative approach is to employ multilayer mirrors whose coating is tailored to reflect a fixed single harmonic from the frequency comb delivered in HHG, 30,36,37 or to select a broad bandwith close to the high-energy cutoff for attosecond spectroscopy.…”