UCL Department of Physics and Astronomy

Prof Steven Bramwell

Prof Steven Bramwell

Professor of Physics and Astronomy

Dept of Physics & Astronomy

Faculty of Maths & Physical Sciences

Joined UCL
1st Aug 1997

Research summary

My research interest is in Model Magnets -- real magnetic systems that approximate idealised models of many-body behaviour.  In the early part of my career I made three significant discoveries: 

* In 1993, along with Peter Holdsworth (Lyon) I used renormalization group methods to calculate a universal and frequently observed critical exponent for magnetic films and other two-dimensional systems (beta = 0.23). This today stands as a textbook result in low dimensional magnetism. 

* In 1997, along with Mark Harris (Edinburgh) I invented the concept of "spin ice", named it, and discovered its experimental realisations among magnetic oxides of the pyrochlore family. Spin ice is a magnet state that defies the Third Law of thermodynamics and supports magnetic monopole excitations. We named on account of its close analogy with the statistical physics of water ice. By 2019 spin ice has been referred to more than 5000 times in the scientific literature. 

* In 1998, with Peter Holdsworth and Jean-François Pinton (Lyon) I established an analogy between magnetic critical behavior and turbulent flow that led to a probability distribution being named after us - the Bramwell-Holdsworth-Pinton (BHP) distribution. This result has stimulated much research into non-equlibrium fluctuations in turbulence, geophysics, astrophysics and beyond. 

More recently I have worked on general critical exponents in two dimensional systems, on magnetic monopoles in spin ice, on magnetic Coulomb phases, on spin ice thin films,  on emergent electrochemistry in magnetism, on demagnetizing factors and on water ice. I have also discovered a new state of condensed matter that I call the "harmonic phase" -- this occurs in spin ice and in polar liquids like water and acetone.  

Teaching summary

I have given more lecture courses at UCL than I can remember -- probably more than my students can remember as well. 

I am currently lecturing on "Order and Excitations in Condensed Matter" (PHAS0075, 4th year).   


Career: After graduating from Oxford University, I was a Junior Research Fellow at Lincoln College Oxford from 1986 - 9; then from 1989 - 1994 I worked as a staff scientist at the Institut Laue-Langevin, Grenoble, conducting neutron scattering experiments and improving my skiing. I joined UCL as a Lecturer in Chemistry in 1994 and was Professor of Physical Chemistry from 2000-2009. In 2009 I became Professor of Physics. I am based in the Department of Physics and Astronomy and the London Centre for Nanotechnology.   I am presently Head of the Condensed Matter and Materials Physics group at UCL and I am a Fellow of the Institute of Physics. 

International honours: I won the 2010 Holweck Prize of the French Société de Physique and the British Institute of Physics, in recognition of my work on model magnets, and I was co-recipient of the 2012 Europhysics Prize (Europe's top prize for condensed matter physics) for the discovery of magnetic monopoles in spin ice. In January 2019 I was awarded an honorary doctorate at the University of Uppsala, Sweden.

UK honours:  I presented the 2012 Wohlfarth Lecture of the IOP and won the 2010 "Research Project of the Year", awarded by Times Higher Research. In the same year I was the only UCL academic named on the Times'  list of the 100 most influential UK scientists. 

Media: I have appeared three times on Radio 4's In our Time programme (most recently discussing "kinetic theory", May 2019) and I have lectured on spin ice at the Cheltenham Science Festival. My work on probability distributions was the subject of a television documentary shown in France and Germany as well as Radio documentary in the UK. In 2016 I appeared live on Sky News explaining the Nobel Prize in Physics and in 2018, I was on the BBC World Services' CrowdScience with Sean Giblin (Cardiff), explaining how magnets work. I have given several lectures to London schools.