Our ability to compress more laser energy into shorter duration pulses, has enabled a dramatic increase in the achievable laser intensity and thus the exploration of new regimes of light-matter interaction. Just beyond the limit reached by state-of-the-art high power petawatt (PW) laser systems (10^22 Wcm^-2) we have predicted the creation of a fundamentally new state in the laboratory – a ‘quantum electrodynamic (QED)-plasma’ - similar to that predicted to exist in pulsar magnetospheres. Here the electromagnetic fields in the laser focus are so strong that plasmas rapidly created there are dominated by the feedback between strong-field QED effects and ultra-relativistic plasma processes: both of which are almost completely unexplored experimentally. Yet the transition to the QED-plasma regime represents the most significant advance in high intensity laser-plasma interactions for several decades and is expected soon, with upcoming multi-PW laser facilities (expected to reach intensities of 10^23-10^24 Wcm^-2). This has led to a whole host of new applications, for example, new schemes for compact electron and ion acceleration and hard radiation sources. The aim of this proposal is the first creation of a QED-plasma in the laboratory. Recently our collaborators employed novel focussing plasma optics on Vulcan PW to reach 3x10^21 Wcm^-2 showing hints of gamma-ray emission by QED processes the plasma for the first time. The QED-plasma regime is thus within reach of PW lasers using this novel technique. Experiments exploiting this technique will form the core of this exciting project.
This project has applications in a broad range of areas from bright, spectrally-tunable source of gamma-rays in the energy range for radiography of dense, fusion relevant materials to accelerating ions to ~hundreds of MeV per nucleon, ideal for hadron cancer therapy.
Our group has world-leading expertise in high intensity laser plasma interactions. The student will be able to tap into this to design and lead experiments at world-leading laser facilities under the guidance of the supervisors. We have excellent links with the Central Laser Facility at the Rutherford Appleton Laboratory and the Center for Ultrafast Optical Science at the University of Michigan, home to the Vulcan PW and Hercules lasers respectively and expect to perform experiments on these at the highest intensities yet reached in laser-plasma interactions, enabling us to truly reach the ultra-relativistic plasma regime for the first time.
While the project will be based at the York Plasma Institute, experimental time is anticipated at national and international laser facilities so the student must be prepared to travel. We would also encourage the student to develop their simulation skills to run predictive and interpretive simulations to compliment the experimental work.
The student will develop team-working and leadership skills working as part of an experimental team. Bringing experiments to a successful conclusion will provide excellent development opportunities for problem-solving and project management skills.
3 year PhD with 3.5 years tuition fees plus stipend (£15,009 for 2019/20).