The bulk magnetic character of materials with some nanometer scale critical material dimension (i.e., grain size, layer thickness, particle size. interparticle separation, rod diameter, nanocontact area) has been found to vary considerably from that found in the same materials lacking that nanoscale structure. The measurements focus on characterizing such novel magnetic behavior and understanding the origin of the new phenomena, so that the relationship between structure, processing, and properties can be established. Such a relationship is needed for industry to take advantage of these new materials. Novel phenomena being investigated include, but are not restricted to, enhanced magnetocaloric effects, unusual magnetic softness, improved magnetic hardness, giant magnetoresistance effects, spintronics, magnetic nanoparticles for medical imaging and disease treatment, ferromagnetism in semiconductors, optical transparency in ferromagnets, superparamagnetism, magnetorheology, and enhanced magneto-optic Kerr effects. In addition to a suite of magnetic measurements, numerous nonmagnetic measurement tools, including x-ray diffraction, electron and optical microscopy, and neutron reflectivity, are studied in this project. As a consequence of this work, very high sensitivity magnetic sensors, low energy loss transformers, room-temperature and low field magnetic refrigerators, higher energy product permanent magnets, transparent ferromagnets, and magnetically adjustable amplifiers may be possible in the future.
Ferromagnetism; Giant magnetoresistance; Magnetic nanoparticles; Magnetic semiconductors; Magnetic structure; Magnetocaloric effect; Nanomagnetism; Nanotechnology; Spintronics; Superparamagnetism;