We use scanning tunneling microscopy and spectroscopy (STM / STS) to determine the surface atomic and electronic structure of materials of interest. We have the unique ability to perform these measurements in reactive gases (oxygen, hydrogen, water vapor) and at elevated temperatures. We use modified Omicron VT-STM/AFM equipment which can also perform atomic force microscopy (AFM) in non-contact mode.
X-ray photoelectron spectroscopy (XPS), in an angle-resolved geometry, is used to analyze the top layers of a material's surface to deduce chemical information- both to detect which elements are present on the surface and their chemical binding environment and laterally-averaged electronic structure. We perform these measurements as a function of temperature, and with surfaces annealed in reactive gases in situ in our analysis chamber.
We use our computer cluster, as well as national supercomputing infrastructures supported by NSF and DOE, to perform simulations at the electronic and atomic level, such as density functional theory (DFT), molecular dynamics (MD), and kinetic Monte Carlo (kMC) calculations.