Stimulated Coherent Emission from Short Electron Bunches in Free Space

• Published in: Physical review letters Vol. 77; no. 8; pp. 1492 - 1495
• Main Authors: Robb, GR, Ginzburg, NS, Phelps, AD, Sergeev, AS
• Format: Journal Article Conference Proceeding
• Language: English
• Published: United States 19-08-1996
• Subjects: BEAM BUNCHING; COHERENT RADIATION; ELECTRON BEAMS; PHYSICS; STIMULATED EMISSION; SUPERRADIANCE
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.77.1492

In previous papers stimulated coherent emission of short electron bunches (superradiance-SR) was considered in the frame of 1-D models. In the present work we study superradiance of an electron bunch which has a finite transverse size in the frame of a 2-D model. This model include effects of optical guiding as well as transverse electromagnetic energy escaping and diffraction. Using a nonstationary parabolic equation we described SR of a sheet shaped electron bunch in free space. It is shown that the radiation is composed of a sequence of e.m. pulses which are diffracted after escaping from the channel formed by the electron beam. This process is accompanied by a progressive increase of the electron efficiency. This enhancement is caused by the phenomenon of permanent self supporting resonance due to the variation of the radiation angle and frequency.