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Controlling and shaping radiation beams is fundamental for a better understanding of radiation-matter interaction and advancing experimental techniques for material characterization at high spatial resolution.In particular, the current trend in the miniaturization of magnetic devices pushes the study of magnetic materials and novel experimental techniques able to investigate them. This is crucial for data storage devices, drug delivery systems, imaging, spintronics, medicine, and robotics applications. The first part of the Thesis investigates engineered radiation beams, particularly electron vortex beams, to study the magnetic properties of materials using Electron Magnetic Circular Dichroism (EMCD) implemented in a Transmission Electron Microscope (TEM). This technique benefits from the high spatial resolution typical of TEMs, allowing element-specific measurements of thin magnetic films.I demonstrate in-situ FeRh magnetic phase transition measurements with nanometric spatial resolution. Besides showing the results of the EMCD experiments, I highlight this technique's advantages, challenges, and limitations. The second part of the Thesis is mainly focused on developing beam profilers, which allow for monitoring particle beams, specifically protons. In fact, all available proton detectors suffer from radiation damage, low spatial resolution, and high costs. Here, I show the development of novel beam profilers, which have been realized with different techniques, such as microfabrication and additive manufacturing techniques. All the prototypes are based on scintillating materials and aim to overcome the limitations of the already existing technologies. In addition, I show their response to a proton beam excitation. The results are encouraging and demonstrate the high spatial resolution and frame rates achievable by these detectors.Such beam monitors would be extremely valuable for fundamental studies. For example, they would provide a tool to study proton vortex beams. On the other hand, they could be applied to medical accelerators designed for proton therapy of tumors.
Sylvain Dunand, Jonathan Emanuel Thomet, Luca Massimiliano Antognini, Matthew James Large