  Molecular beam epitaxy (MBE), a workhorse of the semiconductor industry, has
progressed rapidly in the last few decades in the development of novel
materials. Recent developments in condensed matter and materials physics have
seen the rise of many novel quantum materials that require ultra-clean and
high-quality samples for fundamental studies and applications. Novel
oxide-based quantum materials synthesized using MBE have advanced the
development of the field and materials. In this review, we discuss the recent
progress in new MBE techniques that have enabled synthesis of complex oxides
that exhibit "quantum" phenomena, including superconductivity and topological
electronic states. We show how these techniques have produced breakthroughs in
the synthesis of 4d and 5d oxide films and heterostructures that are of
particular interest as quantum materials. These new techniques in MBE offer a
bright future for the synthesis of ultra-high quality oxide quantum materials.
