Diamond Annual Review 2021/22

58 59 D I A M O N D L I G H T S O U R C E A N N U A L R E V I E W 2 0 2 1 / 2 2 D I A M O N D L I G H T S O U R C E A N N U A L R E V I E W 2 0 2 1 / 2 2 Imaging andMicroscopy Group Paul Quinn, Science Group Leader T he Imaging andMicroscopy Group brings together eight experimental facilities (I08, I08-1, DIAD, I12, I13-1, I13-2, I14 and ePSIC) which use electrons and X-rays to image samples under different experimental conditions across a diverse range of length scales and time scales. Of note this year is that I08-1, the soft X-ray ptychography branchline, and DIAD, the dual imaging and diffraction beamline entered their first year of operations. The I08-1 and DIAD beamlines bring newworld-leading capabilities in high-resolution and correlative imaging to the user community.We are are now ramping up user experiments to bring these newcapabilities, and the insights they provide, to bear on a variety of exciting science problems. The DIAD beamline for Dual Imaging and Diffraction offers two X-ray techniques, full-field radiography/tomography and micro-diffraction, used on the same sample quasi-synchronously. This setup enables in situ characterisation of the 3D microstructure of the material at the same time as its crystallographic phase and/or strain state. X-rays froma 10-pole wiggler are split into two independent beams and then combined at the sample position. Imaging beam can be operated in either pink or monochromatic mode; diffraction is conducted with monochromatic mode. Both beam energies can be chosen independently of each other in an energy range of 8-38 keV. In the summer, DIAD expects the delivery of a dedicated mechanical test rig with integrated tomography capabilities which will be an integral part of the end station and enable a variety of scientific experiments in engineering, materials science, biomaterials and hard tissues, geology and mineralogy. DIAD is part- funded by the University of Birmingham. The beamline is now accepting users. The Scanning X-ray Microscopy (SXM) beamline (I08) is for morphological, elemental and chemical speciation on a broad range of organic-inorganic us to identify nano-sized structures under dynamic conditions. A new robot arm has been installed for high-throughput and remote studies and allows measurements of up to 300 samples. It also allows for large sampling and parametric studies in a range of science areas and the possibility of sample mail-in services. The highest spatial resolution, of 30 nm, is achieved on the coherence branch with ptychographic imaging. Continuous improvements have reduced ptycho-tomography scans from days to less than an hour, and ongoing fly-scanning developments aim to reduce this even further. Ptychography has become now a standard user-friendly experiment. Instrumental upgrades for Bragg-CDI (new detector robot software) expands the experimental capabilities for studying nano-crystalline structures and has been applied successfully in combination with ptychography. I14 is used tomap chemical and structural inhomogeneities in awide range of samples. I14 has expanded its core 2D techniques of X-ray fluorescence, diffraction, X-ray Absorption Near Edge Structure (XANES), differential phase contrast and ptychography to include tomography for volume imaging of elemental, structural and chemical states. A new state of the art nano- positioning stage, installed last year, has enabled significant progress to be made towards in situ experiments in liquid and gas environments. A new EIGER detector will also allow us to reduce measurement times for phase contrast and ptychography by an order of magnitude. The electron Physical Science Imaging Centre (ePSIC) at Diamond consists of two transmission electron microscopes, a JEOL ARM 200 and a JEOL GRAND ARM 300, which were brought to Diamond through a collaboration with Johnson Matthey and the University of Oxford respectively. The ARM 200 is a state-of-the-art probe-corrected analytical microscope capable of atomic resolution electron energy loss and X-ray spectroscopy. The ARM 300 is a dedicated imaging instrument aligned across a wide range of accelerating voltages (30 - 300 keV) and is equipped with an Oxford Instruments X-Max 100 EDX detector. It is both probe and imaging corrected and has numerous detectors, including a small pixel array (512 x 512) fast direct electron detector for low voltage work and a newly installed large pixel array (4K x 4K) fast direct electron detector for high voltage imaging. These combined capabilities make this a unique resource for electronmicroscopywithin theUK.With in situ sample holders, users at ePSIC can perform variable temperature measurements from 100 to 1600 K, apply electrical bias to samples during imaging and transfer samples anaerobically into the microscope. For TEM sample preparation, ePSIC runs a JEOL 4700F focused ion beam microscope with in situ lift out and anaerobic transfer capability. The state-of-the-art instrumentation available at ePSIC attracts both established electron microscopists looking to develop new techniques, and scientistswith limitedprevious electronmicroscopy experience interested in the atomic structure of their samples. The ePSIC facility undertook a 5-year international review which recognised the outstanding work of the facility. To position the facility in the longer term, a wider engagement with the UK electron microscopy community will be undertaken in 2022 with the aim of defining a roadmap for physical science electron microscopy in the UK. interactions in a 250 - 4400 eV photon energy range, and sample investigations under ambient or cryogenic conditions. I08 has a range of applications including biological and biomedical sciences, earth and environmental science, geochemistry, and materials science. The new soft X-ray branchline I08-1 took first users in Oct 2020. Key developments, such as a new detector installation, are currently underway and are essential to allow the beamline to access the intended 250-2000 eV photon energy range. This will importantly provide access to the carbon for specto-ptychography studies and improve image quality and resolution. Developments to deliver cryogenic sample handling are also planned subject to operational and commissioning commitments. The resolution and contrast of I08-1 will provide a step change in imaging and spectro-microscopic performance for soft X-ray imaging at Diamond. Applications for user experiments are now accepted through our standard call. The Joint Engineering, Environmental and Processing (JEEP) beamline (I12) uses a 4.2 T superconducting wiggler to provide polychromatic and monochromatic X-rays in the energy range 53 to 150 keV. These high photon energies provide good penetration through large or dense samples. The beamline offers beam sizes ranging from 50 x 50 μm 2 for diffraction, up to 90 x 25 mm 2 for imaging and tomography. Static objects larger than the available beam can be tomographically imaged using special scanning protocols. The beam characteristics enable the study of macroscale samples that are representative of bulk materials and processes. Another feature of I12 is the ability to use complex, enclosed sample environments without unacceptable attenuation of the beam. X-ray techniques available are radiography, tomography, energy-dispersive diffraction, monochromatic 2D diffraction and scattering. Radiography and tomography are performed predominantly with monochromatic X-rays. Polychromatic beam is reserved for energy-dispersive diffraction or non-routine special requests. I12 has a diverse user community (materials science and engineering; chemical processing; biomedical engineering; geoscience; environmental science; physics; palaeontology) who make full use of the beamline’s capabilities. The beamline’s two flexible experimental hutches allowusers to bring their own rigs and sample chambers. I12 continues to support a wide range of in situ , time resolved experiments, notably in additive manufacturing, materials property testing and chemical processing. It is common for users to combine imaging and diffraction in the same experiment. Almost all tomography scanning is done with constant speed stage rotation, to reduce scan times. This“flyscan”technique has recently been extended to diffraction data collection, if required. The I13 Imaging and Coherence beamline is for multi-scale imaging in the energy range of 6 -20 keV. The achievable resolution ranges from several microns to some tens of nanometers with two branchlines operating independently for this purpose. The Diamond Manchester Imaging branchline performs mainly in-line phase contrast tomography with a strong emphasis on dedicated sample environments. A new full-field microscope using Zernike phase contrast imaging over a field of view of 50-100 μm and a resolution of 50 - 100 nm is now in operation, with a growing user community, allowing The new I08-1 and DIAD beamlines bring newworld leading capabilities in high-resolution and correlative imaging to the user community. We are are now ramping up user experiments to bring these new capabilities, and the insights they provide, to bear on a variety of exciting science problems. The ePSIC teammembers