Symmetry and Correlation Effects on Band Structure Explain the Anomalous Transport Properties of (111) LaAlO_{3}/SrTiO_{3}.

The interface between the two insulating oxides SrTiO_{3} and LaAlO_{3} gives rise to a two-dimensional electron system with intriguing transport phenomena, including superconductivity, which are controllable by a gate. Previous measurements on the (001) interface have shown that the superconducting critical temperature, the Hall density, and the frequency of quantum oscillations, vary nonmonotonically and in a correlated fashion with the gate voltage. In this Letter we experimentally demonstrate that the (111) interface features a qualitatively distinct behavior, in which the frequency of Shubnikov-de Haas oscillations changes monotonically, while the variation of other properties is nonmonotonic albeit uncorrelated.