1. Nanocrystalline Oxides For Integrated, Soft Magnetic Applications D. R. Clarke (PI), UC Santa Barbara, DMR-0203785 The overall intellectual goal of the research has been to determine whether, and under what conditions, nanoparticles of magnetic oxides can be used to improve the performance of dc-dc power converters. These are common magnetic devices used in providing low voltage power to computers and microelectronic devices from standard household electrical power lines. Methods of synthesizing large quantities of high quality ferrite nanoparticles with well defined particle size over a wide range of composition have been developed. Magnetic measurements indicate that they have the low losses and high magnetic permeability required for fabricating high frequency dc-dc power converters. As the end of the grant period is approached, a variety of processes been developed for assembling the nanoparticles into components and shapes that can now be tested under realistic application conditions. In contrast to most other studies of nanoparticles, which is restricted to the unique properties of the particles themselves, the significance of the work is in extending it to bulk, assemblages of nanoparticles with a view to substituting for existing materials with improved performance. During the course of the research several surprising scientific discoveries during the research have been made that have broader impact as described in the next foil. The research is a collaborative GOALI program with Rockwell Scientific, a manufacturer of power converters.

2. Nanocrystalline Oxides For Integrated, Soft Magnetic Applications – Broader Impact D. R. Clarke (PI), UC Santa Barbara, DMR-0203785 In studying nanoparticles in the Ni-Zn ferrite system, it has been discovered that the lattice parameters of the nanoparticles are systematically larger, over the entire solid solution range, than those of the bulk material. Furthermore, there is a direct correlation between this lattice expansion and the difference in saturation magnetization of the nanoparticles from that of the bulk material. The origin of the lattice expansion appears to be a direct consequence of the truncated, and hence reduced, Coulombic interaction between ions in oxides associated with the small number of ions in a nanoparticle. The implication is that this is a fundamental characteristic of all oxide nanoparticles, not just magnetic oxides, which may influence many of their properties. Exciting though this is, undoubtedly, the biggest impact of the research has been the education and training of the graduate students supported by the program, Brian Naughton and Jenny Andrews. In turn, they have had an impact on high-school and undergraduate education by mentoring a high school student, a high school teacher, a community college student and several undergraduates. Interactions with the GOALI partner have also given the graduate students an opportunity to regular visits and make measurements in a vibrant and exciting industrial research laboratory.