

Research Expertise and Interest
physics, phase transition behavior of novel states of matter
Research Description
Research Interests
Professor Birgeneau’s research is primarily concerned with the phases and phase transition behavior of novel states of matter. These include one and two dimensional quantum magnets, liquid crystals, physisorbed and chemisorbed surface monolayers, graphite intercalates, highly disordered magnets and lamellar CuO2 superconductors. He uses primarily neutron and x-ray scattering techniques to probe these systems.
Current Projects
Research follows two general themes. In the first, we are studying the properties of conductors and superconductors which are highly disordered and have reduced dimensionality. We deposit ultra thin films (as thin as one atomic layer) on cold substrates and study their conduction properties. Depending on various properties (thickness, temperature, material) these films can be metallic, insulating or superconducting. Furthermore, using electron beam lithography techniques developed in our laboratory, we can make these films as narrow as ‰ 100Å (only 30 atoms across). This allows studies in both 2 dimensions and one dimension and puts us, at low temperatures, into the quantum mechanical regime. We are extending our work to include ferromagnetic materials.
The second area of study is on high Tc superconductors. Transport, Hall effect and electron tunneling measurements are employed to shed light on the mechanism responsible for superconductivity in these materials. In addition, we are investigating various device ideas employing these novel materials and the physics knowledge we obtain.
These studies incorporate graduate students in physics and materials science as well as undergraduates.