9531638 Giordano Advanced lithographic techniques will be used to make several different types of extremely small metallic structures. These structures, which will have one or more dimensions in the 100 - 300 , will be used to study fundamental problems in condensed matter physics. Issues which will be addressed include the behavior of magnetic impurities near surfaces and in the presence of a disordered environment, quantum mechanical behavior off magnetic domain walls in ferromagnets, and fluctuations near critical points in ultra-small systems. In addition to providing new insights into these fundamental problems, this work should also be relevant to the technological problems associated with advanced micro-fabrication processes, and to high density information storage in magnetic media. %%% This continuing improvements in micro-fabrication techniques, such as those used to make hgth density integrated circuits, provide unique opportunities for basic physics research. Many interesting phenomena occur only in extremely small structures. This work will use small structures as tools to address several fundamental questions in condensed matter physics. These questions include the behavior of magnetic impurities in metals, and the quantum mechanical behavior of domain walls in magnets. This fundamental work is also for technological interest, since the physics that will be elucidated will be relevant to future generations electronic devices. In particular, the work on domain walls will be of direct relevance to high density magnetic storage devices. Moreover, the lithographic methods that will be used are prototypes of the methods that will be required to produce future generations of electronic devices. Progress made now in developing and refining new laboratory scale lithographic techniques may prove useful in the fabrication of the next generation of devices. ***
