Abstract
We calculated the mobility of two-dimensional electron gas along an n-type interface in LaAlO3/SrTiO3 heterostructure using the linearized Boltzmann equation. By solving the Schrödinger equation with the Poisson equation self-consistently, it was found that the interface remained non-conducting up to four unit cells of LaAlO3 film. For five or higher unit cells, the interface became conducting due to the significant overlap between the SrTiO3 conduction band and the LaAlO3 valence band. The electron gas was localized within 7 nm from the interface and multi-subbands were occupied. The calculated mobility matches reasonably well with available experimental data. It was found that the mobility is limited by the remote ionic charged layers in LaAlO3 at low temperature. At high temperature, the polar optical phonon was found to be the dominant scattering center.