Mary H

	Mary H. Upton
	A Brief and General Research Summary
	Electrons that are confined in a very thin film show particle in a box-like electronic states. Electrons in the film are electronically confined in the film by the vacuum barrier on one side and by the semiconductor band gap and band structure on the other. I grow thin metallic films on semiconductor substrates by molecular beam epitaxy and study the electronic structure of the films.
	I measure the electronic structure of the films with photoemission spectroscopy. Monochromatic photons impinge on the sample and excite the bound electrons. The electrons then shoot out of the sample and their momentums are measured. The electronic structure of the thin film can be determined from measuring the momentums of the emitted electrons.
	This graph shows how the electronic structure of a film changes as it gets thicker. Each of the peaks in this graph correspond to a different particle in a box state. As the film gets thicker, different the energy of the states changes, therefore peaks at different thicknesses are at different energies.
	All my experiments are done at the Synchrotron Radiation Center in Stoughton, Wisconsin, a source of high intensity, monochromatic photons.