Paul Gellerson

University Of York

I am a Fusion CDT student supervised by Chris Murphy, and my research is on the use of laser wakefield accelerators as x-ray sources, which may have applications in inertial confinement fusion.

My undergraduate degree was in Chemistry at Oxford University, which I completed in 2023. The 4th year of the degree was dedicated entirely to a research project, for which I worked on development of a laser-induced desorption source for photo-induced reaction dynamics experiments. I found I really enjoyed research and the academic environment, and this inspired me to apply for PhDs. In particular I discovered a passion for experimental physics, which, along with a longstanding interest in fusion energy, led to me choosing the Fusion CDT.

In a laser wakefield accelerator a high intensity laser pulse generates a plasma wave as it propagates through a gas. Electrons can enter this plasma wave and be accelerated rapidly in the wake of the laser. Under the right conditions, these electrons can also oscillate and so produce synchrotron radiation in the x-ray region. The challenge I will be taking on is to optimise wakefield accelerators for generation of these x-rays, and thus create an x-ray ‘laser’. It is already possible to generate high power x-ray laser pulses using x-ray free electron lasers (XFELs), but these require several kilometres of undulators, whereas laser wakefield accelerators may be able to generate the same laser powers over a few metres.