Metal-Ceramic Electromagnetostrictive Nanocomposites for Magnetoelectric Nonreciprocal Impedance Inverter

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

TECHNICAL: In this transformative project, PIs plan to synthesize multi-functional materials (MFM) that (i) posses electro-magnetostriction, (ii) exhibits magnetoelectricity, (iii) works as a non reciprocal impedance inverter, and (iv) displays high mechanical strength. The project will synthesize and investigate the structure-property relationship of these novel electrically controlled magneto-electric (ME) nano-composites. The electrically controlled ME system will be realized by using metal nanoparticles which are magnetostrictive and conductive forming a core-shell structure with the ferromagnetic ferrite. The metal ferromagnetic core-shell particles are embedded in a piezoelectric matrix and sintered together yielding a metal-ceramic nano-composite. In this nano-composite, the applied electric field results in a closed loop current in the metal shell inducing magnetic field in the ferrite core which generates strain through magnetostriction. This strain is converted into electric charge through the piezoelectric phase. The synthesis of the electrically controlled ME nano-composite will lead to the invention of a new passive electrical network component - gyrator - which at present does not exist. In conjunction with TEM, nano-beam electron diffraction and X-ray energy-dispersive spectroscopy with a probe size down to a few nanometers will be used to investigate the role of the metallic layer in the formation of the magnetic and piezoelectric domain structures. An important question that will be answered in this project is related to the understanding of metallic layer thickness effect in the nanometer range on the macroscopic ME properties. Comparative studies of the local ME exchange with corresponding structural investigations by XRD and HREM, will be performed to reveal how inter-phase interfaces and their orientations affect ME exchange. NON-TECHNICAL: The material and device synthesized in this research and education program will have significant impact on the electronics industry by improving performance of various components including passive and active filters or delay lines, magnetic field sensors, current probes, read-only memory device, transducers, electromagnetic pick-ups, and advance the application of metallic nanoparticles. The interdisciplinary research area of ME materials will attract students from several majors including materials science and engineering, electrical engineering, mechanical engineering, and electronics. The PIs' will hire one undergraduate student every summer to work on nano-material synthesis. This exercise will also expose them to the state-of-the-art research facilities. The undergraduate student will be drawn from the college of engineering and funded through the summer scholarships given by The Provost of the university. Minority undergraduate students will be involved in the research through the Society of Hispanic Professional Engineers (SHPE). The PI's will initiate a laboratory component to the course Ferroelectric Devices offered in the Fall Semester at UTA "MSE 5390" addressing the application of magneto-electric material. A focused effort on involvement of young women students in the engineering fields will be conducted through lectures in the high school (UTA - Fort Worth Academic Connection). Broad dissemination of the results will be achieved through journal publications, and conference proceedings. The PI's will organize the symposium "Ferroelectric and MultiFerroic Materials", at annual American Ceramic Society meeting. The application oriented results of the research will be provided to the industrial community through the UTA Piezoelectric Workshop Series which is held every year in last week of January. In this way, this research and education program will provide an integrated contribution to the science and society.