Double-grating monochromatic beamline with ultrafast response for FLASH2 at DESY

Abstract

Edited by M. Zangrando, IOM-CNR and Elettra-Sincrotrone, ItalyKeywords: time-delay-compensated monochromator; diffraction; variable-line-spaced grating; free-electron laser. The preliminary design of a monochromatic beamline for FLASH2 at DESY is presented. The monochromator is tunable in the 50-1000 eV energy range with resolving power higher than 1000 and temporal response below 50 fs over the whole energy range. A time-delay-compensated configuration using the variable-line-spacing monochromator design with two gratings is adopted: the first grating disperses the radiation on its output plane, where the intermediate slit performs the spectral selection; the second grating compensates for the pulse-front tilt and for the spectral dispersion due to diffraction from the first grating.

Design of a time-delay-compensated monochromator for the ARPES endstation at S 3 FEL

“…While utilizing a single grating for the spectral selection, the resolving power R = � 0 =�� � 2.26 |m| N according to the Rayleigh criterion, where N is the number of lines within the beamlines full width at half-maximum (FWHM) of the intensity distribution of the footprint for a Gaussian source (Nicolas & Cocco, 2022). The single-grating monochromator will induce a pulse front tilt at the output according to the K matrix of the VLS grating, which results in the pulse duration broadening that can be expressed as (Poletto et al, 2018;Nicolas & Cocco, 2022;Hu et al, 2023a)…”

Design of a time-delay-compensated monochromator for the ARPES endstation at S 3 FEL

“…While utilizing a single grating for the spectral selection, the resolving power R = � 0 =�� � 2.26 |m| N according to the Rayleigh criterion, where N is the number of lines within the beamlines full width at half-maximum (FWHM) of the intensity distribution of the footprint for a Gaussian source (Nicolas & Cocco, 2022). The single-grating monochromator will induce a pulse front tilt at the output according to the K matrix of the VLS grating, which results in the pulse duration broadening that can be expressed as (Poletto et al, 2018;Nicolas & Cocco, 2022;Hu et al, 2023a)…”

FLASH and the FLASH2020+ project—current status and upgrades for the free-electron laser in Hamburg at DESY

“…FL26 hosts the fixed installation of a reaction microscope (ReMi) provided and supported by the Max-Planck-Institute for nuclear physics in Heidelberg [14]. FL23 is currently under commissioning and features a pulse-elongation-compensating double monochromator [15]. An SDU installation upstream in the FLASH2 hall can serve both beamlines FL24 and FL23 and provides delays up to twenty picoseconds between the split FEL pulses.…”

Spectrally tunable ultrashort monochromatized extreme ultraviolet pulses at 100 kHz

“…2). Existing TDC monochromators have two equally constructed stages with two identical gratings and correspondingly equal input (exit) arm lengths [53]. The use of the aforementioned annular geometry specifically designed for the high average power GHHG beamline, and the limited available laboratory space have motivated the construction of a novel, asymmetric monochromator.…”

Design of a time-delay-compensated monochromator for the ARPES endstation at S 3 FEL

“…While utilizing a single grating for the spectral selection, the resolving power R = � 0 =�� � 2.26 |m| N according to the Rayleigh criterion, where N is the number of lines within the beamlines full width at half-maximum (FWHM) of the intensity distribution of the footprint for a Gaussian source (Nicolas & Cocco, 2022). The single-grating monochromator will induce a pulse front tilt at the output according to the K matrix of the VLS grating, which results in the pulse duration broadening that can be expressed as (Poletto et al, 2018;Nicolas & Cocco, 2022;Hu et al, 2023a)…”

FLASH and the FLASH2020+ project—current status and upgrades for the free-electron laser in Hamburg at DESY

“…FL26 hosts the fixed installation of a reaction microscope (ReMi) provided and supported by the Max-Planck-Institute for nuclear physics in Heidelberg [14]. FL23 is currently under commissioning and features a pulse-elongation-compensating double monochromator [15]. An SDU installation upstream in the FLASH2 hall can serve both beamlines FL24 and FL23 and provides delays up to twenty picoseconds between the split FEL pulses.…”

Spectrally tunable ultrashort monochromatized extreme ultraviolet pulses at 100 kHz

“…2). Existing TDC monochromators have two equally constructed stages with two identical gratings and correspondingly equal input (exit) arm lengths [53]. The use of the aforementioned annular geometry specifically designed for the high average power GHHG beamline, and the limited available laboratory space have motivated the construction of a novel, asymmetric monochromator.…”

Design of a time-delay-compensated monochromator for the ARPES endstation at S 3 FEL

“…While utilizing a single grating for the spectral selection, the resolving power R = � 0 =�� � 2.26 |m| N according to the Rayleigh criterion, where N is the number of lines within the beamlines full width at half-maximum (FWHM) of the intensity distribution of the footprint for a Gaussian source (Nicolas & Cocco, 2022). The single-grating monochromator will induce a pulse front tilt at the output according to the K matrix of the VLS grating, which results in the pulse duration broadening that can be expressed as (Poletto et al, 2018;Nicolas & Cocco, 2022;Hu et al, 2023a)…”

FLASH and the FLASH2020+ project—current status and upgrades for the free-electron laser in Hamburg at DESY

“…FL26 hosts the fixed installation of a reaction microscope (ReMi) provided and supported by the Max-Planck-Institute for nuclear physics in Heidelberg [14]. FL23 is currently under commissioning and features a pulse-elongation-compensating double monochromator [15]. An SDU installation upstream in the FLASH2 hall can serve both beamlines FL24 and FL23 and provides delays up to twenty picoseconds between the split FEL pulses.…”

Spectrally tunable ultrashort monochromatized extreme ultraviolet pulses at 100 kHz

“…2). Existing TDC monochromators have two equally constructed stages with two identical gratings and correspondingly equal input (exit) arm lengths [53]. The use of the aforementioned annular geometry specifically designed for the high average power GHHG beamline, and the limited available laboratory space have motivated the construction of a novel, asymmetric monochromator.…”