Tuning the electrical properties of GdSb thin films by epitaxial strain*

Early studies of rare-earth monopnictide (RE-V) thin films have focused mainly on their applications as buried ohmic contacts for III-V semiconductors, THz emitters and detectors, thermoelectrics, diffusion barriers, and plasmonic heterostructures. Recent predictions of topological semimetallic states and observations of extremely large magnetoresistance (XMR) in RE-Vs, and specifically GdSb, have opened up a new research front aimed at studying the interplay between magnetic ordering and XMR. Here we demonstrate the epitaxial growth and characterization of GdSb thin films with thickness varied from 3-60 nm and biaxial strains ranging from -2% to +2% lattice-mismatch. Utilizing x-ray diffraction, in-vacuo angle-resolved photoemission spectroscopy, SQUID magnetometry and magnetotransport measurements we map out shifts in energy bands and trends in exchange interaction parameters due to dimensional confinement and biaxial strain.