Plasma apertures opened up by ASAIL
ASAIL researchers have shown that laser pulses can open a ‘relativistic plasma aperture’ in thin foils, and that diffraction through this aperture can be used to control the flow of charged particles in the plasma.
The new paper, published this month in the prestigious Nature Physics journal, also shows that by changing the polarisation of the laser, the motion of plasma electrons can be manipulated.
Prof Paul McKenna of the University of Strathclyde said: “Our discovery opens a new pathway to controlling charged particle dynamics. The results have immediate application in the development of laser-driven ion sources and can potentially be used to model astrophysical phenomena such as helical field structures in jets originating from the rotation of black hole accretion disks”.
By manipulating the polarisation of the laser, the team found they could produce helical structures – plasma twists – which could potentially have uses across a range of areas of research, including in the field of medical physics and radiotherapy.
The experiment was performed using the Gemini laser at the Central Laser Facility and the simulations were carried out using the ARCHIE-WeSt (University of Strathclyde) and ARCHER (Edinburgh) high performance computers.
The research is supported by EPSRC funding for the ASAIL Project.
Details of the paper can be found here.
19 January 2016