John Wilkinson

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John Wilkinson

DPhil Student

John is a DPhil researcher, working in Steve Blundell's muon group. He is interested in using the technique of Muon Spin Rotation (µSR) (see here for more information) to analyse ionic fluorides. He is also involved in outreach, by helping to present Levitate! and presenting his own presentation, Magnificent Muons: Uncovering the Secrets of the Universe, 2 Millionths of a Second at a Time, which gives the audience a tour of the physics of muons, from their discovery to their usage in research today.

Fluorine is the most electronegative element, so antimuons, used in µSR experiments, are strongly attracted to them. As such, the spin of the muon enters into an entangled state with the fluorine nucleus (often referred to as an F--μ--F state), which can be measured by observing the time-dependance of the muon polarisation, which gives a beats-like precession signal. This signal is found to be heavily dependent on the geometry of the F--μ--F state, meaning we can learn a lot about how the muon behaves inside materials by studying it.

Often though, the muon's precession-like signal is found to relax, which has previously been fit with a phenomological relaxation function, but we have found recently (J.M Wilkinson and S.J Blundell, Phys. Rev. Lett. 125, 087201 (2020)) that this relaxation is actually due to the muon also entering into an entangled state with the surrounding nuclei as well as the fluorines, which means we can use these F--μ--F states to learn about the way in which surrounding nuclei behave, as well as the fluorines. My research aims to develop techniques to allow us to analyse such systems, using ideas from quantum information and many-body quantum physics.

I am currently the B6 Condensed Matter Physics tutor at New College. Previously, I have been involved in demonstrating 2nd/3rd year Thermal/condensed matter labs, and 1st year general physics labs.