Multibeam and Collective Effects in Laser Fusion Plasmas – Plasma Strand Project

Supervisors: Nigel Woolsey (University of York) & Kevin Glize (STFC-CLF).

The principal method for generating energy from fusion using lasers involves compressing nuclear fuel with lasers and then heating a central region to thermonuclear temperatures. The National Ignition Facility Fusion has confirmed this approach to inertial fusion approach by achieving ignition and burn of a fusion plasma. A major challenge is understanding the instabilities that arise when intense lasers, such as those used at NIF, interact with a plasma. These laser-plasma instabilities or LPIs limit the efficient compression of millimetre-sized spheres containing deuterium and tritium.

The aim of this PhD (Fusion CDT) project is to study LPIs – experimentally and computationally – and more specifically multibeam and collective processes associated with stimulated Raman scattering (SRS) and two plasmon decay (TPD) instabilities. This will build on the laser plasma instability research developing at the York Plasma Institute and involves collaborations with several research partners including the UK’s Central Laser Facility and the Institute of Laser Energetics at the University of Rochester, USA.

The PhD student will work with postdocs and other students to combine experimental research at leading large-scale laser plasma facilities in the UK and internationally to make novel measurements and then use this information to test computational models of SRS and TPD. At the York Plasma Institute, optical fibre-based instruments are being developed to measure angular resolved signatures of these instabilities and associated hot electron spectra. These techniques will be suitable for high-repetition rate, single beam, and larger single-shot, multibeam laser facilities. The computational approach includes a recently developed ray-trace approach that uses steady-state analytic theory for SRS and TPD and other instabilities to create a standalone model or one that can be coupled to hydrodynamic simulations.  The model enables calculations of the simultaneous growth and saturation of these instabilities and includes models for plasma refraction.  The student would be involved with extending this model to enable comparison with experimental measurements.

The image above shows an SRS measurement across 24 fibre-based sensors placed around a laser driven target. This type of measurement illustrates the loss of laser energy needed to drive an implosion.

This project will be based in York, with many opportunities to visit and collaborate with staff at national and international laboratories. These visits will be a week or more and there are opportunities for longer stays.

During the first six months of the PhD, students will typically travel to undertake taught modules at all of the Fusion CDT partner universities.

This project is offered by University of York. For further information please contact: Nigel Woolsey (nigel.woolsey@york.ac.uk).

This project may be compatible with part time study, please contact the project supervisors if you are interested in exploring this.

For details on how to apply, please visit: Apply