Terahertz/Infrared radiation: from the production with accelerator based sources to the use in material characterization for accelerator cavities

Terahertz/IR radiation and technologies have found incredible development in the last few decades due to their applications in many different fields, ranging from indoor and outdoor communication, security, environmental monitoring, biological research, medical applications and finally as a spectroscopic investigation tool in condensed matter. However, many of these applications requires increasingly high power sources and demands for the possibility to manipulate radiation features such as pulse time duration, frequency spectrum and polarization. One of the most efficient ways of generating THz/IR radiation fulfilling these requirements is to use relativistic electrons accelerated in storage rings, where synchrotron radiation can be generated by means of bending magnets or specific Insertion Devices (IDs), or by accelerating electrons in LINACs, where the development of FEL technologies allows for coherent and monochromatic radiation to be produced. This thesis project presents a dual approach to the design and use of accelerators as radiation sources. The first and the second part of this work are dedicated to the study of the emission of THz/IR radiation from both Synchrotrons and Linacs, starting from the simulation of the interaction of electron beams with magnetic optics and IDs, moving to the characterization of the emitted radiation and finally arriving at the design of extraction beamlines to guarantee the use of the produced radiation in external user facilities. The third part of the project represents a bridge between materials science and THz/IR optics with accelerator physics by proposing the study of new materials suitable for the development of accelerator technologies and necessary to overcome accelerators limitations and costs.