Speaker
Mr
James Cowley
(University of Oxford)
Description
In multiple-pulse laser wakefield acceleration (MP-LWFA), a train of laser pulses spaced by the plasma period is used to drive a plasma wave, rather than the single pulse used in most experiments. Driving wakefields with a train of low-energy pulses has several advantages: laser-driven plasma accelerators can exploit new laser technologies which cannot deliver high-energy pulses, but which can provide ultrafast, few-mJ pulses at kHz repetition rates with high wall-plug efficiency; in principle the properties of each pulse in the train can be tuned to optimize the wake amplitude; the reduced peak intensity of each pulse could allow the use of smaller optical components; and the architecture naturally lends itself to recovery of energy left in the wakefield by a second pulse train separated from the first by an odd number of half plasma periods.
We report progress on the first experiments to observe MP-LWFA, using the Astra laser at the Rutherford Appleton Laboratory. The experiments employ frequency-domain holography to measure the wake amplitude as a function of the properties of the pulse train and target plasma, enabling studies of the effects of detuning from resonance and of ion motion.
Primary author
Mr
James Cowley
(University of Oxford)
Co-authors
Mr
Christopher Arran
(University of Oxford)
Mr
Christopher Thornton
(JAI)
Mr
Gavin Cheung
(University of Oxford)
Dr
Laura Corner
(JAI, Oxford University)
Dr
Nicolas Matlis
(N/A)
Mr
Robert Shalloo
(JAI, University of Oxford)
Prof.
Roman Walczak
(University of Oxford)
Prof.
Simon Hooker
(University of Oxford)
