Non-Linear Terahertz Electronics with Self Organized Rare-Earth Arsenide Semi-Metal/Semiconductor Composites

摘要

A new materials arena has been opened for quantum electron transport devicesbased on magnetic, semi-metal compound semiconductor heterostructures. Epitaxial ultrathin films of a rare earth arsenide, ErAs, were grown in GaAs semiconductors. The dissimilarities between the ErAs, a magnetic semimetal, and the compound semiconductor make possible the fabrication of three terminal resonant tunneling transistors with ultra thin semi-metal quantum wells. Resonant tunneling through semi-metal quantum wells was observed for the first time. A strong coupling of the magnetization and the resonant tunneling was discovered that demonstrates magnetization controlled resonant tunneling. Nano-composites of ErAs / GaAs were also grown. Electron transport in these systems exhibits giant magnetoresistance magnetization controlled island to island electron hopping transport. This research program has opened the possibility of high density, non-volatile information storage and processing based on magnetic, semi-metallic, quantum structures grown and integrated into compound semiconductor heterostructures.