MRI: Development of a femtosecond angle-resolved electron spectroscopy system for mapping the 3D electronic structures and responses of functional materials and nanostructures

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The ability to control and engineer complex materials and nanostructures is essential for enabling an array of technologies including: solar-energy harvesting, solar to fuel conversion, heat recovery, and the development of novel photoactive nanostructured materials and nanoelectronics devices used in computing and internet infrastructure. This project will overcome widely recognized major bottlenecks to progress by addressing the scarcity of experimental data on the changes of local properties in these functional materials or devices. This is enabled by using innovative accelerator-based approaches to manipulate the probe's dynamical properties to significantly enhance the intensity and time-resolution of an ultrafast electron probe system. The high-throughput of the present system is the ideal probe for unveiling transient photochemical processes due to its high sensitivity to charge states and its more direct accesses to local electronic structures and electron dynamics for pinpointing the origins of these local, transient electronic processes. Furthermore, the present system advantageously provides three-dimensional spectroscopy by high-energy beams that penetrate the bulk of samples and the ability to sample large energy dispersion and momentum distributions. These new capabilities are also relevant to understanding an array of complex materials issues of broad interest, including studies of high-temperature superconductors, phase transitions, and novel electronic switching devices. Scientific and technological progress will be enabled by a unique team of experts in accelerator and beam physics, radiofrequency cavity design and construction, femtosecond (one quadrillionth, or one millionth of one billionth, of a second) laser and electron beam technologies, and theoretical modeling for the development of this unique ultrahigh speed electron beam system. The outcome of this MRI will be potentially transformative for addressing Grand Challenge Problems in nanoscience and nanotechnology that are critical to the industrial and applied sector, in areas ranging from catalysis to photovoltaics and material synthesis. We envision that the successful development of such a technology will lead to a new generation of electron-based ultrafast spectroscopy systems that are economical enough to be widely replicated in individual industry or university-based laboratories .A novel ultrafast high-brightness electron spectrometer system will be designed and implemented to achieve high sensitivity and combined high momentum-energy resolution through innovative active energy compression technology to preserve the throughput of the femtosecond photo-activated electron beam. The new system, a prototype ultrafast angle-resolved electron spectroscopy system, will be the first of its kind to provide element-sensitive spectroscopic imaging of three-dimensional electronic structures in complex and nanostructured materials at ultrafast timescales. The new capabilities will provide needed high throughput, and access to bulk crystalline materials. Significantly broader reach in energy scales will be available, covering the entire Brillouin Zone of quantum and complex materials with three-dimensional electronic structures, thus providing a more universal method than existing approaches. It is also targeted to substantially enhance the temporal-momentum resolution and throughput of electron-based spectroscopy systems to ultimately allow studies of individual nanostructures and motifs. The resulting spectrometer will be well-suited for characterizing; radiation effects in materials, defects, and photo-responses in plasmonic and photovoltaic nanostructures; phase transitions of superconductors and complex, strongly correlated electron materials; and exploring novel phases of matter in extreme environments. Scientific and technological progress will be enabled by a unique team of experts in accelerator and beam physics, radiofrequency cavity design and construction, femtosecond laser and electron beam technologies, and theoretical modeling for the development of this unique femtosecond electron beam system. The outcome of this MRI will be potentially transformative for investigating ultrafast physical, chemical and materials electronic processes to understand and identify the emerging and functional properties of complex, nanostructured materials and devices for addressing Grand Challenge Problems in condensed matter physics, materials and chemistry. Such a capability is also of interest to the industrial and applied sector, in areas ranging from catalysis to photovoltaics and material synthesis. It is envisioned that the successful development of such a technology will lead to a new generation of electron-based ultrafast spectroscopy systems that are economical enough to be widely replicated in individual industrial or university-based laboratories for ultrafast materials research.