Resonant Tunneling and Hot Electron Spectroscopy in Buried Rare-EarthArsenide/Semiconductor Heterostructures

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 magneto-resistance, 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.