Dr. Marvin A. Schofield
Electron holography carried out in a field-emission TEM offers the possibility for quantitative analysis of electric and magnetic structures at the nanometer scale. The underlying phenomenon behind holography is the coherent interference of the beam electrons in the TEM, so that the electron phase may be recovered. The electron phase carries direct information about the electric and magnetic field distribution in the sample that is normally lost with conventional microscopy techniques. My main interest is the application of electron holography to quantitative measurements of electrostatic and magnetostatic potential distributions in a variety of material systems, and especially how those measurements relate to specific material properties and functionality. My primary focus has been on strongly-correlated electron systems, including grain boundaries in high-Tc superconductors (BNL press release and Bulletin article), and ferromagnetic and ferroelectric properties of mixed-valence manganite systems. Mapping of magnetic field distribution associated with patterned magnetic elements (BNL press release and Bulletin article) and magnetic nano-particles is also a region of focus as these structures represent basic building blocks of nano-structured magnetic devices.
Back to "Members"