Magnetic Tunable Nanostructures: Property Characterization and Modeling

George Washington University, Washington DC

Investigators

Abstract

The objective of this research is to systematically determine the magnetic properties of nanoscaled ferromagnetic materials and to compare them to their coarse-grained counterparts for use as electronically tunable magnetic nanostructures. The research involves synthesis, processing, and characterization of their magnetic properties as a function of material variables and applied electric field. These results, complemented by modeling will provide a fundamental understanding of the effects of electric field, chemistry, and microstructure on the properties of magnetic tunable nanostructures. The synthesis involves an eight source molecular beam epitaxy and an eight-target DC/RF sputtering deposition systems, with in-situ characterization capabilities. Their magnetic properties (MS, MR, HC, Hb, and TC, First Order Reversal Curves, etc.) will be characterized using SQUID and SQUID VSM magnetometers, Lorentz microscopy, FMR, and Kerr Effect spectroscopy. The microstructural features will be examined by LEED, TEM, STEM, XRD, Lorentz and Mössbauer spectroscopies. The results will advance the understanding of these nanostructures and promote their technological applications. This is a German-American collaborative effort, involving the Institute of Nanotechnology, Karlsruhe, Germany with George Washington University, Washington, DC and the National Institute of Standards and Technology, Gaithersburg, MD. If successful, the results of this research are expected not only to promote the understanding of tunable nanostructures, but also impact the understanding of the magnetic behavior of the broader class of magnetic nanostructures that include tunnel junctions, quantum dots, and patterned media. Future efforts are expected to lead to tailoring and optimization of the properties of various magnetic nanostructures for their use in a wide range of technological applications, including magnetic data storage and sensor devices. Graduate and undergraduate students and post-doctoral fellows will benefit through acquiring comprehension in advanced experimental magnetic measurements and taking opportunities to exchange visits between the U.S. and Germany. This project is funded jointly by the Division of Civil, Mechanical, and Manufacturing Innovation and the Office of International Science and Engineering.