A new high-resolution spectrometer for Fermi surface studies

Our ability to understand the behaviour of metals and metallic systems relies heavily on our knowledge of the behaviour of the electrons they contain. Metals can be considered as a collection of positively charged nuclei held together by an electron glue , where the electrons are free to wander freely between the nulcei. Our understanding of simple metals like copper is very good even though it based on a very simple treatment of the way in which the electrons interact with each other and the nuclei. However, there is a class of materials where this simple description breaks down. In these materials, the motion of the each electrons is strongly correlated with that of the others - we call these strongly correlated electron systems. By making measurements of the momentum of the electrons, we can substantially improve our understanding of these materials, and test the latest theories that have been developed to understand them. The kinds of materials which we are interested in looking at range from superconductors to technologically important alloys such as Al-Li.Our research relies on us being able to accurately determine the angle between gamma rays, and that means we need to know where they hit our detectors as precisely as possible. We would like to acquire a pair of position-sensitive detectors that offer a resolution about five times smaller than we currently have. This would enable us to perform many new experiments that would be impossible without this improvement in resolution.