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Full-Text Articles in Physics
Femtosecond Free-Electron Laser By Chirped Pulse Amplification, L.H. Yu, E. Johnson, D. Li, Donald P. Umstadter
Femtosecond Free-Electron Laser By Chirped Pulse Amplification, L.H. Yu, E. Johnson, D. Li, Donald P. Umstadter
Donald Umstadter Publications
In this work we combine elements of chirped pulse amplification techniques, now familiar in solid-state lasers, with an amplifier based upon a seeded free-electron laser (FEL). The resulting device would produce amplified pulses of unprecedented brevity at wavelengths shorter than can be currently obtained by any tunable laser system. We use a subharmonically seeded FEL to illustrate the concept. Radiation from a Ti:sapphire laser is frequency tripled and stretched optically to provide a coherent seed pulse for the FEL. When coupled to an electron beam inside a magnetic wiggler, the seed radiation introduces an additional energy modulation on the electron …
Nonlinear Plasma Waves Resonantly Driven By Optimized Laser Pulse Trains, Donald Umstadter, Eric Esarey, J. Kim
Nonlinear Plasma Waves Resonantly Driven By Optimized Laser Pulse Trains, Donald Umstadter, Eric Esarey, J. Kim
Donald Umstadter Publications
A method for generating large-amplitude plasma waves, which utilizes an optimized train of independently adjustable, intense laser pulses, is discussed and analyzed. Both the pulse widths and interpulse spacings are optimally determined such that resonance is maintained and the plasma wave amplitude is maximized. By mitigating the effects of both phase and resonant detuning, and by reducing laser-plasma instabilities, the use of appropriately tailored multiple laser pulses is a highly advantageous technique for accelerating electrons. Practical methods of producing the required pulse trains are suggested.
Ultrashort Ultraviolet Free-Electron Lasers, Donald Umstadter, L. H. Yu, E. Johnson, D. Li
Ultrashort Ultraviolet Free-Electron Lasers, Donald Umstadter, L. H. Yu, E. Johnson, D. Li
Donald Umstadter Publications
In this work we combine elements of chirped pulse amplification (CPA) techniques, now familiar in solid-state lasers, with an amplifier based upon a seeded free-electron laser (FEL), The resulting device would produce amplified pulses of unprecedented brevity at wavelengths shorter than can be currently obtained by any tunable laser system. We use a subharmonically seeded FEL to illustrate the concept. Radiation from a Ti:sapphire laser is frequency-tripled and stretched optically to provide a coherent seed pulse for the FEL. When coupled to an electron beam inside a magnetic wiggler, the seed radiation introduces an additional energy modulation on the electron …