Magnetism, Superconductivity and Pseudogap at the LaAlO$_{3}$-SrTiO$_{3}$ Interface

The electron liquid at the LaAlO$_{3}$-SrTiO$_{3}$ interface is a two-dimensional superconductor and simultaneously displays magnetic order. To experimentally explore the fundamental properties of this state, we developed a planar tunnel junction technology that allows to measure the spectral density-of-states of the superconducting liquid while its carrier density can be altered by the electric-field effect. These studies yield surprising results, as key features of the superconducting electron liquid at the LaAlO$_{3}$-SrTiO$_{3}$ interface are found to be analogous to features deemed characteristic for the high-$T_{\mathrm{c}}$ cuprates. This work was performed in collaboration with C. Richter, H. Boschker, W. Dietsche, E. Fillis-Tsirakis, R. Jany, F. Loder, L.F. Kourkoutis, D.A. Muller, J.R. Kirtley, and C.W. Schneider.