The behavior of several different types of ultra-small condensed matter systems will be investigated. One set of experiments will study electronic motion in metals such as the behavior of magnetic impurities in small metal systems, the electrical resistance of magnetic domains and domain walls in very narrow ferromagnetic wires, and electron phase coherence times at very low temperatures. A second body of work will investigate the motion of fluids in very small structures. New methods for the fabrication of fluid "containers" as small as a few hundred angstroms on a side will be developed to obtain information on the nature of viscous flow at extremely short length scales. The central theme of this work is the use of ultra-small structures as tools with which to study fundamental issues in condensed matter physics. %%% This project will study several different types of ultra-small systems. One set of experiments will explore electronic motion in metals, with particular attention to how this motion is affected by the magnetic properties of the metal. Another body of work will develop new methods for the fabrication of fluid "containers" as small as a hundred atomic diameters on a side. These will be used to investigate atomistic effects on the flow of simple fluids. The central theme of this work is the use of ultra-small structures as tools with which to study fundamental issues in condensed matter physics. ***
