Profile

Im a cisgender gay physicist, who lives in oxford with my boyfriend of 7 years. I’m a competitive powerlifter, and I watch all 4 Alien films and all of Star Trek Voyager at least once a year. I have four tattoos, two piercings, and my pronouns are he/him

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I specialise in the scattering of x-rays and neutrons from magnetic materials at the atomic level. most every-day solid materials have a regular structure at the atomic scale where each of the atoms sit at fixed distances from each other in a pattern that repeats in space. We call this a crystal, and you can see what this looks like for Sodium Chloride (table salt) here:

When a material is magnetic, it means that some of the atoms in the material have what is called a Permanent Magnetic Moment – this is the atomic scale version of behaving like a fridge magnet with a north and a south pole. It comes from an intrinsic property of electrons called Spin, which is very important to quantum mechanics and particle physics. If all of the atomic magnetic moments have a well-defined relationship to each other, then we say that the material is Magnetically Ordered. You can see how this looks for the simple magnet Nickel Oxide here where the arrow points in the direction of the atomic north pole:

The blue and red atoms are Nickel, while the yellow ones are oxygen.

When we scatter a beam of neutrons or x-rays from a crystal, the way that they bounce off tells us almost everything we need to know about the way the atoms and their magnetic moments are arranged inside the crystal. Of course, this is not always easy to work out!

Below, you can see scattering of neutrons above and below the temperature at which manganese oxide becomes magnetic – when it is magnetic, there are extra peaks! Only neutrons can see magnetism like this, to the x-rays it is invisible. These simple experimental results were so amazing at the time that it was enough to earn Clifford Shull the 1994 Nobel Prize in physics.

I have 4 main jobs: To do research (experiment, analyse data, write scientific articles), to communicate that research (going to conferences and giving talks), to inspire other people about science and being a scientist (I often give talks about what it’s like to be a gay physicist), and to teach Oxford University undergraduates.

I spend a lot of time teaching students at oxford university about the interaction between atoms and how this gives rise to the properties of materials, as well as thermodynamics (the theory of heat and energy and how it gets transferred) and how you can use statistics to understand and model large collections of objects.

Most of the rest of my time is spent preparing for experiments, doing experiments, or analysing the data from my experiments. The kinds of experiments I do involve going to large facilities like the Rutherford Appleton Laboratory (first picture) or the Swiss Lightsource (second picture)

While I’m at these places, i place my crystals in front of the beam of x-rays and neutrons to scatter off them, using a big instrument like the one picture below (the MAPS spectrometer at the ISIS Neutron and Muon facility). The big blue detector panels record all the neutrons that hit them, and this allows me to construct images like the one on the left, which is the signal that you get as neutrons scatter from a crystal of Yttrium Iron Garnet (Y3Fe5O12) compared to a model I created for the magnetic interactions between iron atoms in this material.