Rare-Earth Based Compounds and Self Assembled Nanostructures
Novel Electronic/Topological/Magnetic Properties
Recent predictions of topological semimetallic states and observations of extremely large magnetoresistance (XMR) in RE-Vs, and specifically GdSb and LuSb, have opened up a new research front aimed at investigating the interplay between magnetic ordering and XMR. We have studied the origin of these properties in LuSb and studied their tunability through dimensional confinement.
Relevant Publications
Weak antilocalization in quasi-two-dimensional electronic states of epitaxial LuSb thin films
Epitaxial III-V based nanocomposites
Epitaxial III-V based nanocomposites are comprised of small rare-earth monopnictides (RE-V) nanoparticles embedded in thermoelectric semiconductor alloys during MBE growth. The inclusion of nanoparticles increases the number of interfaces leading to an increase in phonon scattering and a decrease in thermal conductivity. In addition, these particular nanoparticles are believed to provide enhanced electrical conduction through electron filtering mechanisms. RE-V materials are primarily cubic materials with the rock-salt crystal structure and have lattice parameters commensurate with many of the III-V based semiconductors. The RE-V materials are thermodynamically stable with their III-V semiconductor counterparts and the rare-earth elements have low solubilities in the host semiconductors leading to the precipitation of nanoparticles at relatively low concentrations. This supports the growth of single crystal, low dislocation density nanocomposites with coherent interfaces for electron conduction and phonon scattering.
Relevant Publications
Lattice distortion in single crystal rare-earth arsenide/GaAs nanocomposites
Size effects on the electronic structure of ErSb nanoparticles embedded in the GaSb(001) surface
