School of Physics, Engineering and Technology
- School of Physics, Engineering and Technology
- York Plasma Institute
- Research
- Matter at the extremes
- High Intensity Laser Matter Interactions
High Intensity Laser Matter Interactions
Contact person: Chris Ridgers
Current high-power lasers focus light to intensities up to 10^23 times higher than the intensity of sunlight at the surface of the Earth. At these extreme intensities the electrons are quickly stripped from the atoms in any matter in the laser focus, generating a plasma. However, as intensities increase from the peak reached today (2x10^22W/cm^2) to those expected to be reached on next-generation facilities such as the Extreme Light Infrastructure (>10^23W/cm^2), due to become operational soon, the behaviour of this plasma dramatically alters. At intensities >5x10^22W/cm^-2 the electromagnetic fields in the laser focus are so strong that quantum electrodynamics effects become important. For example, an avalanche of antimatter production can ensue with strong consequences for the behaviour of the plasma as a whole. We work on the basic theory of laser propagation and absorption in these 'QED-plasmas' and underpinning experiments measuring the rates of the important QED processes for the first time. We are working towards the first generation of a QED plasma, usually only seen in extreme astrophysical environments such as pulsar magnetospheres, in the laboratory. The image is taken from large-scale simulations of ion acceleration (ion density in blue) by the laser (grey) in a QED-plasma - a pair plasma (green) forms in front of the initial electron (red)- ion plasma, absorbing the laser pulse and quenching the ion acceleration.