Ultrashort pulse filamentation and monoenergetic electron beam production in lwfas

A.G.R. Thomas, S.P.D. Mangles, C.D. Murphy, A.E. Dangor, P.S. Foster, J.G. Gallacher, D.A. Jaroszynski, C. Kamperidis

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

In the experiments reported here, the filamentation of ultrashort laser pulses, due to non-optimal choice of focusing geometry and/or electron number density, has a severely deleterious effect on monoenergetic electron beam production in laser wakefield accelerators. Interactions with relatively small focal spots, w0 < λp/2, and with pulse length cτ λp, incur fragmentation into a large number of low power filaments. These filaments are modulated with a density dependent size of, on average, close to λp. The break-up of the driving pulse results in shorter interaction lengths, compared with larger focal spots, and broad energy-spread electron beams, which are not useful for applications. Filamentation of the pulse occurs because the strongly dynamic focusing (small f-number) of the laser prevents pulse length compression before reaching its minimum spot-size, which results in non-spherical focusing gradients.
Original languageEnglish
JournalPlasma Physics and Controlled Fusion
Volume51
Issue number2
DOIs
Publication statusPublished - Feb 2009

Keywords

  • ultrashort pulse filamentation
  • monoenergetic electron beam production
  • lwfas

Fingerprint Dive into the research topics of 'Ultrashort pulse filamentation and monoenergetic electron beam production in lwfas'. Together they form a unique fingerprint.

Cite this