High Mobility and Scattering Mechanisms in La-doped BaSnO$_{\mathrm{3}}$ Films Grown by a Radical-based Oxide MBE Approach

Using experiment and transport modeling, we will present on the detailed electronic transport study of La-doped BaSnO$_{\mathrm{3}}$ films grown \textit{via} a radical-based oxide MBE approach. Using a chemical precursor of tin, effusion cell for Ba and rf plasma for oxygen, we will first present the discovery of an ``MBE growth window'', in which cation stoichiometry of BaSnO$_{\mathrm{3}}$ films was maintained as 1:1 for a range of Ba/Sn flux ratios. Temperature dependent electronic transport measurements were then performed to investigate the effect of La doping on mobility ($\mu )$ and carrier concentrations (n) in stoichiometric BaSnO$_{\mathrm{3}}$ films grown on SrTiO$_{\mathrm{3}}$ (001) substrates. We will discuss the role of charged dislocations, non-stoichiometry and dopant density on the electronic transport properties. Using \textit{ab initio} calculation and Boltzmann transport equations, temperature-dependent mobility and Seebeck coefficient are calculated and will be presented to elucidate different mobility-limiting scattering mechanisms as a function of n and temperature.