The implementation of full-field transmission X-ray microscopy (TXM) at X-ray tube sources suffers from image blurring due to the chromatic aberration of the lenses and from long exposure times due to the inherent low flux of laboratory sources. Here, we demonstrate the first laboratory full-field TXM system, which combines tailored monocapillary optics, an achromatic X-ray lens, and the M & Ouml;NCH hybrid silicon pixel detector to address these challenges. With current optics, this TXM system demonstrates a spatial resolution down to 480 nm using X-ray energies around 10 keV. Despite the large pixel pitch of the M & Ouml;NCH detector, high spatial resolution imaging can be achieved by using interpolation methods leveraging charge sharing. In addition, the energy resolving power of the M & Ouml;NCH detector allows for the acquisition of elemental information. Bridging the gap between structural and elemental characterizations using X-rays, the concept of this laboratory X-ray microscope provides new opportunities for research in the fields of material science, environmental science, and biology. (c) 2026 Chinese Laser Press

Hierarchical zeolites have become benchmark catalysts in reactions such as methanol-to-hydrocarbons and selective oxidations, owing to their enhanced diffusion, improved accessibility to acid sites, and extended lifetimes relative to their purely microporous counterparts. Among them, ZSM-5 stands out for its structural stability and tunable acidity. However, characterising the spatial distribution of porosity within individual crystals remains challenging. Conventional techniques either lack internal spatial resolution or require destructive sample preparation, limiting their ability to resolve intracrystalline heterogeneity. Here, we employ ptychography X-ray Computed Tomography (PXCT) to non-destructively visualise and quantify the internal porosity in hierarchical ZSM-5 crystals. Experiments were carried out at the Caterete beamline of the 4th generation SIRIUS synchrotron (LNLS/CNPEM), achieving three-dimensional resolution of 40 nm. The 3D volume reveals spatially heterogeneous porous networks, including core-shell-like structures and porosity gradients introduced by post-synthetic desilication. This study highlights the potential of PXCT for the advanced characterisation of porous catalysts. Beyond enabling direct visualisation of the porosity architecture, the method provides structural insights relevant for interpreting diffusion behaviour, reactivity patterns, and deactivation mechanisms. PXCT opens new possibilities for the rational design of porous catalysts, allowing spatial correlations between synthesis, structure, and function to be experimentally resolved.

Full-field transmission X-ray microscopy (TXM) is a powerful technique for nondestructive nanoscale imaging. In laboratory-based systems, high-resolution full-field TXM remains challenging due to the low brightness and polychromaticity of X-ray tubes. Here, we demonstrate a laboratory TXM instrument composed of a microfocus X-ray source with an integrated multilayer Montel mirror, high-resolution Fresnel zone plates (FZPs), and a charge-integrating direct conversion hybrid pixel detector (M & Ouml;NCH detector). The Montel mirror monochromatizes the X-ray beam and efficiently focuses it onto the sample. Importantly, the numerical aperture of the Montel mirror is matched to that of an FZP with an outermost zone width of 25 nm, thereby ensuring optimal performance in spatial resolution. A central innovation of our work is the replacement of traditional scintillator-based indirect detection schemes with a direct conversion hybrid pixel detector featuring higher detective quantum efficiency. This transition is enabled by the uniquely small pixel size of the M & Ouml;NCH detector (25 & micro;m) and its interpolation capabilities arising from charge sharing between contiguous pixels when an X-ray photon is detected. By integrating our tailored TXM design with the advanced interpolation capabilities of the M & Ouml;NCH detector, features with dimensions down to 34 nm were resolved. Furthermore, the microscope can be operated in Zernike phase-contrast mode, which was applied for imaging of an integrated-circuit chip. This work represents a significant step forward in laboratory-based TXM, introducing a combination of X-ray optics that brings nanoscale imaging in laboratory and industrial environments closer to synchrotron-level resolution. (c) 2026 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

We demonstrate two-dimensional (2-D) imaging and resonant inelastic X-ray scattering (RIXS) spectroscopy in the hν 2 “mapping” scheme using a reflection zone plate (RZP) at soft X-rays. Experiments at the PETRA III storage ring (DESY) around the N K α line (392.4 eV) verify that an RZP can be used in the paraxial regime combined with the 1-D line scanning mode for time-efficient full-field imaging of an extended object with an angular size of 2.5 mrad at low aberrations, even for off-design energies, at a spatial resolution of (14–24) μ m. A similar setup collects the RIXS spectra of acetonitrile within (388.6–401.8) eV for a variable incident photon energy between 399 eV and 400 eV, at a potential resolution of (0.3 ± 0.1) eV. RZPs with their precise manufacturability, efficiency, and strong dispersion can serve as advantageous diffractive optical elements in soft X-ray microscopy or “photon-in vs. photon-out” spectroscopy.

Recent progress in ultrafast x-ray sources helped establish x-rays as an important tool for probing lattice and magnetic dynamics initiated by femtosecond optical pulses. Here, we explore the potential of ultrashort hard x-ray pulses for driving magnetic dynamics. We use a transient grating technique in which a spatially periodic x-ray excitation pattern gives rise to material excitations at a well-defined wave vector, whose dynamics are monitored via diffraction of an optical probe pulse. The excitation of a ferrimagnetic gadolinium bismuth iron garnet film placed in an external tilted magnetic field by x-rays at the Gd L3 edge results in both magnetic and non-magnetic transient gratings whose contributions to the diffracted signal are separated by polarization analysis. We observe the magnetization precession at both longitudinal acoustic and spin wave frequencies. An analysis with the Landau-Lifshitz-Gilbert equation indicates that the magnetization precession is driven by strain resulting from thermal expansion induced by absorbed x-rays. The results establish x-ray transient gratings as a tool for driving coherent phonons and magnons, with the potential of accessing wave vectors across the entire Brillouin zone.

We present a nested Wolter-I mirror design for a neutron condenser, which is based on established X-ray telescope technology. We demonstrate through simulations that it can increase the flux density at the ESS imaging instrument ODIN by up to two orders of magnitude. Experimental measurements of reflectivity and figure errors on a prototype mirror element confirm the technical feasibility of the approach. Then, we introduce design strategies for an imaging objective to fully exploit the condenser specifications while achieving spatial resolutions comparable to those of X-ray micro-computed tomography instruments. Analytically, we show that for monochromatic beams suitable solutions exist employing arrays of hundreds of identical objectives, realized either as compound refractive lenses (CRLs) or Fresnel zone plates (FZPs). To mitigate the inherent chromatic aberration of these optics, each individual objective could be replaced by an achromatic FZP/CRL combination. Key optical properties of the resulting microscope are estimated. This novel full-field microscopy concept for highly divergent, polychromatic neutron beams has the potential to improve temporal and spatial resolution for large samples and sample environments and to enable the simultaneous acquisition of hundreds of projections in neutron tomography.

Ultrafast optical laser-based techniques have enabled the probing of atomistic processes at their intrinsic temporal scales with femto- and attosecond resolution. However, the long wavelengths of optical lasers have prevented their interrogation and manipulation with nanoscale spatial specificity. Advances in hard X-ray free-electron lasers have enabled progress in developing X-ray transient-grating spectroscopy, a technique that aims to coherently control elementary excitations with nanoscale X-ray standing waves. Thus far, the realization of this technique at the nanoscale has been a challenge. Here we demonstrate X-ray transient-grating spectroscopy with spatial periods of the order of 10 nm via the subfemtosecond synchronization of two hard X-ray pump pulses at a precisely controlled crossing angle. This creates a thermal grating and preferentially excites coherent longitudinal acoustic phonon modes with the transient-grating wavevector. On probing with a third, variably delayed, X-ray pulse with the same photon energy, time-and-wavevector-resolved measurements of the modulation of the induced scattering intensity provide evidence of ballistic thermal transport at nanometre scales. These results highlight the potential of X-ray transient gratings as a powerful platform for studying nanoscale transport in condensed matter and the coherent control of nanoscale dynamics. Applications of optical laser-based techniques are limited by the long wavelengths of the lasers. Now, observations of phonons and thermal transport at nanometre length scales are reported with an all-hard X-ray transient-grating spectroscopy technique.

Time-resolved X-ray absorption spectroscopy (TRXAS) at the Co L 3 -edge was used to identify metal-centered (MC) character in the S 1 excited state of cyanocobalamin (CNCbl). Cobalamins have UV/visible spectra that are dominated by intense corrin-based excitations, but these ligand-centered states energetically overlap with charge transfer and MC excited states that may be populated following photoexcitation. Ultrafast optical and hard X-ray spectroscopy have shown that CNCbl forms a structurally distorted S 1 state, but these probes lack a clear signature of the S 1 electronic identity, which theory has suggested is a ligand-to-metal charge transfer (LMCT) state. Femtosecond soft X-ray TRXAS offers greater state-selectivity than many optical or hard X-ray probes, but has, so far, been limited to highly concentrated (≥100 mM) samples. A new experimental setup at the European X-ray Free Electron Laser (EuXFEL) that enables studies of sub-10 mM samples and provides ∼100 fs time-resolution is used to measure the TRXAS of CNCbl at the Co L 3 -edge. Comparison of the L 3 -edge XAS spectrum measured at 0.8 ps with ligand field multiplet simulations indicates that the S 1 state is primarily a MC excited state. The sub-20 µOD detection sensitivity achieved in this study demonstrates the possibility of applying this method to a wide range of naturally-occurring and synthetic transition metal complexes.

Dark-field X-ray imaging visualizes structural inhomogeneities through small-angle scattering, but existing directional methods are confined to the micrometer scale. While recent advances have extended dark-field capabilities to nanoscale transmission X-ray microscopy, directional scattering retrieval - critical for characterizing anisotropic nanostructures - has remained inaccessible for imaging resolutions in the sub-micrometer scale. Here, we demonstrate the first directional dark-field setup for nanoimaging, achieving orientation mapping of scattering features below the spatial resolution limit. Our method is experimentally simple to implement with existing transmission X-ray microscopy setups. We validate its performance by successfully resolving sub-resolution test structure orientations, cross-correlating orientational changes within hierarchical nanoporous materials, and mapping the directional arrangement of hydroxyapatite nanocrystals 30 - 70 nm within human tooth enamel. By utilizing shadow regions in the optical configuration, we further extend the detectable scattering vector range, demonstrating a pathway toward size-selective dark-field imaging. This advancement enables the quantitative structural characterization of anisotropic nanomaterials, which are critical to biomineralization, advanced materials, and nanotechnology applications.

The paper presents a comprehensive description of a new setup implemented and commissioned at the SEXTANTS beamline of Synchrotron SOLEIL for absorption and scattering experiments with X-ray beams carrying an orbital angular momentum, also known as twisted X-ray beams. Two alternative methods have been implemented, based on the use of either spiral zone plates or fork grating devices, and we show how they can be used for both defining and assessing the orbital angular momentum of an X-ray beam. We also demonstrate that cascading multiple devices enables integer operations on the orbital angular momentum of the resulting X-ray beam. Finally, we report the results of the first resonant scattering pilot experiments in transmission and reflection mode, intended to assess the feasibility of future users' measurements. The availability of twisted soft X-rays complements the range of experimental techniques in elastic, resonant and coherent scattering available at the SEXTANTS beamline.

Abstract Neutrons provide exceptional insight into materials, owing to their sensitivity to light elements, isotopic composition, magnetic moments, and high-penetration. However, neutron sources are polychromatic and of low brightness. Neutron optics provides a route to address these limitations by focusing, and to date, various types of neutron optics have been developed based on reflection, refraction, diffraction, and magnetism. Notably, compound refractive lenses and Fresnel zone plates have been demonstrated for imaging, yet their severe chromatic aberration under polychromatic beams has prevented their widespread use and limits progress towards true high-resolution neutron microscopy. Here, we demonstrate an achromatic neutron lens for full-field neutron microscopy. This development overcomes the intrinsic sample-detector distance constraint in pinhole-based radiography. The lens magnification enables the use of efficient detection systems without loss of spatial resolution and establishes a pathway towards high-resolution neutron microscopy. We anticipate the neutron achromat will advance a broad range of neutron methods.

Neutrons provide exceptional insight into the structure and dynamics of materials, owing to their sensitivity to light elements, isotopic composition, magnetic moments, and high-penetration capabilities. Neutron sources produce beams that are polychromatic and have low brightness. Neutron optics provides a promising route to mitigate these challenges by guiding and focusing neutron beams, and to date, various types of neutron optics have been developed based on reflection, refraction, diffraction, and magnetism. Notably, compound refractive lenses and Fresnel zone plates have also been demonstrated for imaging and focusing applications, yet their severe chromatic aberration under polychromatic beams has prevented their widespread use and continues to limit progress towards true high-resolution neutron microscopy. Here, we demonstrate an achromatic neutron lens combining a compound refractive lens and a Fresnel zone plate. We experimentally verify its achromatic behaviour and compare its performance to a Fresnel zone plate. We employ the achromatic neutron lens to realise a full-field neutron microscope. This development overcomes the long-standing trade-off between flux and spatial resolution that constrains neutron imaging in a pinhole-based radiography geometry and establishes a pathway towards high-resolution neutron microscopy. We anticipate that this new class of neutron optics will advance a broad range of neutron methods that require or benefit from focused neutron beams.

For the integration of two-dimensional materials in future devices, a fundamental understanding of their response to external stimuli is needed. Toward this goal, we have investigated the electron and spin dynamics in the metallic van der Waals material Fe3GeTe2 (FGT) in its paramagnetic state after ultrafast optical excitation. To this end, we have employed a zone plate streaking technique with probing energies in the extreme ultraviolet range, tuned to the Fe M2,3 and Te N4,5 absorption edges. This approach provides insights into energy-dependent charge dynamics with a sensitivity to transient absorption changes on the order of ∼ 10 - 4 . We find a slow carrier relaxation time at both elemental edges-up to ( 2.2 ± 0.6 )  ps in Te and exceeding several picoseconds in Fe-which is surprising for a metal. To elucidate the complex time-resolved response, we also employ static x-ray absorption spectroscopy at the corresponding elemental edges, in which we find a double feature at the Fe M2,3 edge. We attribute this to different Fe sites in the pristine material and an oxidized surface layer, and we propose that the time-resolved absorption dynamics show a mixture of signals stemming from the different species. Additionally, we conducted time-resolved x-ray magnetic circular dichroism measurements in FGT at room temperature. We do not find clear evidence of the previously observed light-induced ferromagnetic order above T C . Our study lays the groundwork for a deeper understanding of charge and spin dynamics in FGT after optical excitation as part of a roadmap for 2D spintronics.

Many neutron techniques can greatly benefit from enhanced neutron lenses for focusing and imaging. In this work, we revisit the potential of diffractive optics for neutron beams, building on advanced high-resolution nano-lithography techniques developed for the fabrication of X-ray diffractive optics used at synchrotron facilities. We demonstrate state-of-the-art fabrication of nickel and silicon Fresnel zone plates and we report proof-of-concept experiments for full-field neutron microscopy and small angle neutron scattering. The advancement of neutron diffractive optics will open new opportunities for neutron techniques, improving both the efficiency and resolution of existing instruments.

Maintaining the highest quality and output of photon science in the VUV-, EUV-, soft-, and tender-x-ray energy ranges requires high-quality blazed profile gratings. Currently, their availability is critical due to technological challenges and limited manufacturing resources. In this work, we show the developed method for manufacturing blazed gratings relevant for synchrotron-based science by means of electron-beam lithography (EBL). We investigate different parameters influencing the optical performance of blazed profile gratings and develop a robust process for the manufacturing of high-quality blazed gratings using polymethyl methacrylate as a high resolution positive tone resist and ion beam etching. Finally, we demonstrate excellent agreement in efficiency between the produced EBL grating and the theoretical prediction.

We present a systematic investigation of the optical response to circularly polarized illumination in twisted stacked plasmonic nanostructures. The system consists in two identical, parallel gold triskelia, centrally aligned and rotated at a certain angle relative to each other. Sample fabrication was accomplished through a novel multilevel high-resolution electron beam lithography. This stack holds two plasmonic modes of multipolar character in the near-infrared range, showing a strong dependence of their excitation intensities on the handedness of the circularly polarized incident light. This translates into a large circular dichroism which can be modulated by adjusting the twist angle of the stack. Fourier-transform infrared (FTIR) spectroscopy and numerical simulations were employed to characterize the spectral features of the modes. Remarkably, in contrast to previous results in other stacked nanostructures, the system’s response exhibits a behavior analogous to that of two interacting dipoles only at small angles. As the angle approaches 15°, where maximum dichroism is observed, more complex modes of the stack emerge. These modes evolve towards two in-phase multipolar excitations of the two triskelia as the angle increases up to 60°. Finally, simulations for a triangular array of such stacked elements show a sharp mode arising from the hybridization of a surface lattice resonance with the low-energy mode of the stack. This hybridized mode demonstrates the capability to be selectively switched on and off through the light polarization handedness.

Maintaining the highest quality and output of photon science in the VUV-, EUV-, soft- and tender-X-ray energy ranges requires high-quality blazed profile gratings. Currently, their availability is critical due to technological challenges and limited manufacturing resources. In this work we discuss the opportunity of an alternative method to manufacture blazed gratings by means of electron-beam lithography (EBL). We investigate the different parameters influencing the optical performance of blazed profile gratings produced by EBL and develop a robust process for the manufacturing of high-quality blazed gratings using polymethyl methacrylate (PMMA) as high resolution, positive tone resist and ion beam etching.

We present advanced electron beam lithography (EBL) strategies for the fabrication of high-precision variable-line-spacing (VLS) x-ray gratings with sub-nanometer pitch control on large, curved silicon substrates up to 140 × 30 × 10 mm3. Our approach employs a novel non-linear dose mapping methodology, combining dynamic field scaling and multi-pass writing techniques with HSQ resist to enable precise control over pitch. The resulting grayscale lithography resist patterns are transformed into blazed grating profiles via through-mask oxidation, which leverages different silicon oxidation rates for accurate topography transfer. The implementation of newly developed dose gradient shapes dramatically improves data handling efficiency and promotes stable, reliable exposures. We validate our methods experimentally through laser goniometer measurements, which confirm a third order polynomial line density agreement between designed and fabricated pitches across the optical area of 120 × 20 mm2. Unlike mechanical ruling, where throughput decreases with increasing line density, our EBL approach maintains constant throughput regardless of the grating line density, providing unique flexibility not limited to single lines but also allows for complex freeform x-ray optics in the future. This work thus demonstrates the scalable fabrication of high-quality x-ray VLS gratings, advancing the prospects for next-generation optical components at synchrotrons and free-electron lasers.

Optical-domain transient grating (TG) spectroscopy is the ideal tool to investigate transport phenomena in gases, liquids and solids, but it is limited to typically micron-size grating periods. Extreme-Ultraviolet TG has represented a major leap forward to access the mesoscopic scales. Hard X-ray TGs open access in principle to the nanoscale. Hard X-ray TGs were recently generated using the Talbot effect and probed by optical pulses, but these hinder exploiting the advantages of the nanoscale gratings. Here, we present an all-X-ray TG study, in which few-femtosecond hard X-ray pulses are used both for excitation and probing. Our experiment was performed on an amorphous film of an FeGd alloy and on a thin silicon single crystal. The results show a manifestation of the TG induced by the X-ray pump and probe pulses in the form of Talbot carpets, as well as temporal evolution of the grating in crystalline silicon showing coherent optical phonons. Ultrafast all-X-ray TG spectroscopy has the potential to study fundamental excitations with femtosecond time resolution and nanometer spatial sensitivity.

We present a series of novel X-ray imaging systems designed specifically for the soft X-ray energy range, optimized for operation in ultra-high-vacuum environments and compactness. These systems achieve micrometre-level spatial resolution with high collection efficiency of visible light by using high numerical aperture optics. Comprehensive characterization of the systems' response was performed, including linearity assessments and X-ray sensitivity measurements, across X-ray photon densities ranging from 1 nJ m−2 to 10−4 nJ m−2. The imaging system was employed for caustic measurements to characterize the X-ray focal spot and to demonstrate its capabilities. Finally, grating interferometry was used to measure the wavefront distortion, yielding a pitch resolution as fine as 3.1 µm. These results underscore the system's potential for high-resolution soft X-ray imaging and wavefront characterization applications.