Nanomagnetism is one of the most active areas in science with a wide range of fundamental scientific problems as well as important and emerging technologies. New functionality requires control of magnetic order at the nanometer spatial scale and sub-nanosecond temporal (time) scale. Within this project, the interplay of strain and magnetism in nano-structured magnetic materials and the control of these properties to yield new functionality are being studied. Researchers are combining novel materials engineering and synthesis approaches with advanced synchrotron techniques for three-dimensional strain and piezoelectric imaging to probe the response of nanoscale systems to perturbation by magnetic and electric fields. The goal is to gain a fundamental understanding of strain in nanostructured materials. This project will benefit from strong collaborations with international, national user facility and industrial scientists. This interactive approach provides important educational and post-graduate career opportunities for both graduate and undergraduate students. In addition the project includes outreach efforts aimed at middle-school and high-school students via the Young Physicist Program at the University of California San-Diego (UCSD) and The Winston School in Del Mar, and outreach at the undergraduate level, via UCSD's Society of Physics Students.
TECHNICAL DETAILS: The first part of the project probes the fundamental magnetostrictive response of nano-materials of magnetic transition metals and transition-metal oxides. In doing so, thin-film heterostructures, core-shell nanowires and nanoparticles are being imaged by coherent X-ray diffraction techniques to obtain quantitative three-dimensional nano-scale images of the magnetostriction and then link the magneto-elastic response to the microstructure and micromagnetic states. This research then uses strain to obtain and optimize giant magnetostriction in nanostructures materials. In the next stage, materials are being integrated into devices to actively control the strain, magnetic, transport and magneto-optical responses with a combination of magnetic and electric fields. Finally, the response of strain at the ultrafast timescales using synchrotron-based pump-probe techniques probes the systems with electric, magnetic or thermal pulses and images the response with nano-focused and/or coherent X-ray diffraction techniques.
