Synthesis and characterization of half-metallic ferromagnetic oxides for organic semiconductor spintronic devices

University Of California-Riverside, Riverside CA

Investigators

Abstract

Abstract ECCS-0802214 J. Shi, U of Cal Riverside The objective of this research is to synthesize, characterize, and engineer high spin polarization ferromagnetic/organic interfaces for high-efficiency spin injection, and to fabricate lateral spin valve devices using organic semiconductors as spacer. The approach is to synthesize and fabricate devices with manganite-based half-metallic ferromagnetic electrodes which possess nearly 100% spin polarization. To characterize the half-metallic property of the spin injecting electrodes, two unique methods will be employed: second harmonic generation and tunneling magnetoresistance, both probing the electronic and magnetic properties of the ferromagnetic/organic interfaces. Intellectual merit: Ideal half-metallic ferromagnets should have 100% spin polarization, which can serve as the most efficient spin injector in spintronic devices. In real devices, the interface can significantly differ from the bulk. In particular, the interfacial magnetism has not yet been adequately addressed. In addition, spin diffusion and decoherence in organic materials have not been systematically studied for lacking effective experimental tools. These topics are the focus of this proposed research. Advances in synthesis and characterization of the half-metallic ferromagnetic materials and in fundamental understanding of the spin-dependent process in organic materials will not only undoubtedly enrich our knowledge of materials, but also benefit other disciplines of condensed matter physics and materials science. Broader impact: The proposed research is related to high-efficiency spin injection in spintronic devices such as recording heads, non-volatile memories, and light-emitting devices. If the spin injection efficiency is dramatically increased by using half-metallic ferromagnetic injectors, the resulting devices will perform superior to the existing devices. High-efficiency devices can lead to a significant saving in energy and a lower production cost, which will positively impact the high-technology industry and the society as a whole. The proposed education plan will involve more women and under-represented minorities in research, continue the outreach activities to local middle and high schools and the surrounding communities, and enhance information exchange between the research community and the general public. These proposed activities will also raise public?s interest level in science and encourage the college-bound students to choose science as their careers.