The next generation of nuclear fusion reactors rely on state-of-the-art high temperature superconductors (HTS) to achieve very high magnetic fields, the superconductor of choice being (RE)Ba2Cu3O7 (RE = rare earth element). Under operation in a fusion device the superconductor is exposed to high energy neutrons which degrade the material. This eventually leads to total loss of the superconducting state. Crucially, this happens long before any structural damage can be observed with atomic resolution electron microscopy. Currently, little is known about the stability and evolution of these irradiation induced defects, and their impact on material properties.
This project will build on our previous work combining X-ray absorption spectroscopy (XAS) and density-functional theory (DFT) which has suggested Frenkel defects are present [Commun Mater 3, 52 (2022)]. In this project we will investigate the formation of other possible defect structures and their time evolution. This will be done using molecular dynamics with machine-learned interatomic potentials. The defect structures, and their predicted spectra will be used to interpret XAS experimental data from irradiated samples.
Any questions concerning the project can be addressed to Prof Rebecca Nicholls (rebecca.nicholls@materials.ox.ac.uk) and Prof Jonathan Yates (jonathan.yates@materials.ox.ac.uk).
General enquiries on how to apply can be made by e mail to graduate.studies@materials.ox.ac.uk. You must complete the standard Oxford University Application for Graduate Studies. Further information and an electronic copy of the application form can be found at https://www.ox.ac.uk/admissions/graduate/applying-to-oxford.