Investigation of Nanoscale Electronic Properties and Transport in Semiconductors and Magnetic Materials

University Of California-San Diego, La Jolla CA

Investigators

Abstract

This project addresses research centered on III-V nitride heterostructures and spin-dependent transport in magnetic materials. The approach employs proximal probes(scanning capacitance and tunneling microscopies), as well as a conducting proximal probe tip to perform local photoconductivity measurements for characterization of local electronic structure and charge transport properties in semiconductor and magnetic materials. The aim is to increase understanding of the nature and influence of defects and other structural features on material properties and device performance, serving to inform strategies for optimization of material quality and epitaxial layer design for a variety of device applications. Investigation of magnetic thin-film materials will focus on the development and application of spin-polarized current-voltage and conductance spectroscopy in combination with atomic and magnetic force microscopy to characterize spin-polarized current injection and spin-dependent carrier transport in magnetic thin-film materials. The approach allows studies at lengths scales as small as a few tens of nm of phenomena such as spin-polarized current injection into a variety of magnetic and magnetoresistive thin-film materials, spin-dependent carrier transport across single magnetic domain walls, and the detailed nature of spin-dependent tunneling processes in ferromagnet-insulator-ferromagnet tunnel junctions. %%% The project addresses basic research issues in topical areas of materials science with high technological relevance. High priority will be placed on training of graduate students in advanced nano-characterization techniques of increasing importance in modern materials and device engineering. In addition, the connection between studies of basic material properties and their role in device engineering and applications will be emphasized, thereby affording students opportunities for interaction with other university and industrial researchers working in related areas. ***