Active research is being pursued for alternatives to our current silicon technology and transition metal oxides heterostructures are valuable in this respect since they can now be engineered in a Lego-like fashion. It has been shown that their interfaces are not only conducting but that they also exhibit ferroelectricity, superconductivity, gate tunable transport, large thermoelectric effect, large spin-orbit contributions, possibly ferromagnetism as well. Given this multifunctionality, oxide electronics (we coined it "oxitronics") appears to be a promising lead for new types of components, notably in regards to spintronics.
We shall focus on a particular oxide based heterostructure, LaAlO3-SrTiO3 (LAO-STO). Experiments reveal that a quasi two-dimensional metallic sheet that evolves at low temperature into a superconducting state may form on the STO side, close to the interface. Charge transport can be controlled by applying gate voltages. Strain and spin also control the transport of charge; the possibility to tune the strength of the interfacial spin-orbit interaction (Rashba) is promising in this respect. The existence of a two-dimensional topological metallic state was theoretically proposed in this system and fingerprints of this regime have recently been experimentally revealed through a giant spin to charge conversion (inverse Rashba-Edelstein effect).
M. Vivek et al., Phys. Rev. B 95, 165117 (2017)
A Spin-Orbit Playground: Surfaces and Interfaces of Transition Metal Oxides
S Gariglio, A D Caviglia, J-M Triscone, M Gabay, Reports of Progress in Physics, 82, 012501(2019)
A coffee break will be served at 11h00.