Molecular beam epitaxy growth of SmB$_{6\pm\delta}$ thin films

SmB$_6$ has emerged as a leading candidate in the search for exotic topological states generated by strong interactions. The synthesis of epitaxial SmB$_6$ thin films presents new avenues to control surface termination, thickness, and strain in this system. In this work, we use molecular beam epitaxy (MBE) to deposit SmB$_{6\pm\delta}$ films on insulating (001)-oriented MgO substrates. We use ex-situ x-ray diffraction and magnetotransport measurements to assess the properties of the samples and compare them to previously reported values for single crystals. We also discuss the prospects of using rare-earth substitution to control the correlation strength and alter the topology of the bulk and surface electronic states.