Generation and Amplification of Coherent Radiation with Optical Orbital Angular Momentum in a Free-Electron Laser

Free-electron lasers (FELs) are state-of-the-art devices that use highly energetic electron beams to generate coherent, frequency-tunable, high-brightness light for a broad range of applications. In this PhD dissertation, an new method of FEL operation is proposed and theoretically examined in which the electron beam is prearranged to emit higher-order light modes that carry orbital angular momentum about their axis of propagation. This scheme shows promise for opening new regimes in modern light source based research. Results from a proof-of-principle experiment based on this concept are also presented.