Understanding the mechanical limitations of the performance of soft X-ray monochromators at MAX IV laboratory

Abstract

MAX IV is a fourth‐generation, or diffraction‐limited, synchrotron light source with a number of state‐of‐the‐art beamlines. The performance of a beamline is, to a high degree, set by the energy resolution it can achieve, which in turn is governed to a large extent by the monochromator. During the design phase of a monochromator, the mechanical requirements must be fully understood and met with margin. During commissioning, the performance must be verified and optimized. In this paper, six soft X‐ray monochromators at MAX IV beamlines (Bloch, Veritas, HIPPIE, SPECIES, FinEstBeAMS and SoftiMAX) are examined with a focus on their resolving power, energy range and the time required to change measurement range, as those parameters are dependent on each other. The monochromators have a modern commercial design, planned and developed in close collaboration with the vendors. This paper aims to present the current status of the commissioning at MAX IV with emphasis on elucidating the mechanical limitations on the performance of the monochromators. It contains analysis of the outcome and our approach to achieve fast and high‐resolution monochromators.

Spin- and time-resolved photoelectron spectroscopy and diffraction studies using time-of-flight momentum microscopes

“…The required energy resolution (10 meV range) and momentum resolution (∼1% of the size of the BZ) challenge the performance of the beamline (resolving power is E/ΔE ≈ 10 5 ) and the angular resolution of the electron detector (<0.1°). Advances of the brilliance of synchrotron sources show up in a number of soft-x-ray beamlines with high resolving powers (several 10 4 ), e.g., P04 140 (PETRA III), ADDRESS 141 (Swiss Light Source), TEMPO 142 (SOLEIL), BL17SU, BL23SU, BL25SU [143][144][145] (SPring8), I09 146 (DIAMOND) and VERITAS 147 (MAX IV). The photoemission cross sections decrease with increasing energy in the soft (and hard) X-ray regime, 148 demanding high recording efficiency.…”

An ultra-high-stability four-axis ultra-high-vacuum sample manipulator

“…Veritas and Species are two resonant inelastic X-ray scattering (RIXS) beamlines at MAX IV Laboratory, Lund, Sweden, that operate in the energy range 30-1500 eV (Sa ˚the et al, 2020; Urpelainen et al, 2017;Sjo ¨blom et al, 2020). RIXS is a technique used in a broad range of applications (Schmitt et al, 2014;Rubensson, 2015;Rubensson et al, 2013;Nordgren & Rubensson, 2013) but in recent years the use of RIXS in the study of correlated materials has led to an expansive build up of high-resolution soft X-ray RIXS beamlines world wide (Schmitt et al, 2013;Brookes et al, 2018;Diamond Light Source, 2020;Jarrige et al, 2018;Dvorak et al, 2016), where the main focus has been the study of solid samples.…”

Opportunities of Advanced Physical Studies at the Hefei Advanced Light Facility

“…Maintaining a high energy resolution requires mechanical stability and the precise control of various instruments. [49][50][51][52] Beamlines demand the development and implementation of advanced diagnosis techniques, precise focusing systems, and high-quality mirrors, which are crucial to achieve high spatial resolution and high coherence. [53,54] To enhance experimental efficiency, developing new algorithms and software tools for data analysis and visualization are required.…”