This project is a systematic study of magnetism and charge inhomogeneity in nanoscale thin films of complex oxides, with a goal of using the unique properties of films as a tool to uncover basic materials physics. Over the last decades, studies of complex oxides have uncovered rich behavior that allows for interesting properties but presents great difficulties in understanding the basic controlling physics. An emerging picture in the study of these materials is the ubiquitous presence of inhomogeneity at several different length scales. There are several important experimental degrees of freedom that can be exploited in the study of films: strain, epitaxy, finite size effects, and the creation of artificial multilayer lattices. We will use these parameters to better understand the interplay between magnetism, charge ordering, and electronic phase separation. This work will require significant development of our ability to control the oxygen content in oxide films and to measure the oxygen that has been incorporated. It will build the infrastructure for oxide film studies at the University of Connecticut, further collaborations with NIST and Brookhaven National Laboratory, and help train both students and Connecticut area high school science teachers.
This project will take advantage of the considerable technology that has been developed recently to control properties of nanoscale films of functional oxide materials in order to better understand the fundamental physics of these materials. Functional oxide materials have surprising and extremely useful properties, but they are not well understood at a basic level. Films the thickness of a few nanometers can be different from the same material in bulk form for many reasons including a change in the typical atom to atom distances, the extreme thinness of the film can induce effects from quantum mechanics, and new properties can arise by layering films of different compounds on top of each other. Each of these effects can serve as a control parameter to test basic theories. This work will require significant development of the ability to control and measure the amount of oxygen in the films. It will build the infrastructure for nanoscale film studies at the University of Connecticut, further collaborations with NIST and Brookhaven National Laboratory, and help train students. At least one high school science teacher will work with the group each summer to further her/his scientific training and then be able to bring the research frontier back into the classroom.
