Electronic transport in thin films of BaPbO3: Unraveling two-dimensional quantum effects

Recently, perovskite-related BaPbO3 has attracted attention due to its hidden topological properties and, moreover, has been used as a thin layer in heterostructures to induce two-dimensional superconductivity. Here we investigate the normal-state electronic transport properties of thin films of BaPbO3. Temperature- and magneticfield-dependent sheet resistances are strongly affected by two-dimensional quantum effects. Our analysis decodes the interplay of spin-orbit coupling, disorder, and electron-electron interaction in this compound. Like for recently discussed topological materials, we find that weak antilocalization is the dominant protagonist in magnetotransport, whereas electron-electron interactions play a pronounced role in the temperature dependence. A systematic understanding of these quantum effects is essential to allow for accurate control of properties not only of thin films of BaPbO3 but also of topological heterostructures.