Strongly correlated electron physics in novel materials

The basic physical theories of matter have been known for many decades but increasingly scientists are uncovering materials that challenge some of these accepted tenets, and within these new classes of compounds there is considerable potential for technological innovation. However, before we can run we must walk and a full understanding of the physics of these novel properties is required so the materials can be bent to our will. Notably, recent research has pointed to glaring errors in our standard theory of metals, the underlying cause of which are strong interactions between the constituent electrons. Traditionally, electron-electron interactions have been treated as negligible within metals and generally ignored. However, over the last few decades novel materials have been uncovered in which electron interaction energies are comparable to the electronic kinetic (or translational) energies; the electrons are said to be 'strongly correlated'. As well as appearing to defy the standard theories of metals these systems quite often display striking magnetic phenomena. A particularly exciting aspect is that these phenomena offer us excellent opportunities for technological development. Indeed, several new correlated electron systems discovered in the last few decades have been adapted for solid state devices. Examples include substations for mobile phone networks that incorporate the high-Tc cuprate superconductors and new magnetic read head technologies that exploit the giant magnetoresistance properties of the Fe/Cr/Fe trilayers. This scientific research proposal is centred on producing and studying exotic materials with the goal of discovering new correlated electron quantum states. It focuses two unexplored families of materials, the niobates and iridates that we believe should provide new and interesting avenues of research in the correlated electron field. The research is fundamental in nature but benefits from a very clear connection to electronic device development since new electronic quantum phenomena offer excellent opportunities for applied science.On a broader view, the physics of materials represents a new frontier for scientific pioneering. Physicists are analogous to the intrepid explorers who, in their thirst for discovery and adventure, set out to explore and map the world. In their course of their adventures, those pioneers discovered some startling facts about our planet that challenged many long-held conceptual viewpoints, for example the world was not flat, as had been previously supposed, but spherical. In a similar manner (although with considerably less danger!), we hope to uncover exciting new phenomena that challenge our current perceptions of nature and enhance our understanding of the universe that we live in. It is this thrill of discovery that drives people in materials physics to explore and quantify strange new compounds that will hopefully one day benefit all.