The life of electrons in quantum materials: navigating conflicting effects and forming new phases of matter

Scientists have been exploiting the quantum character of matter for a long time. For example, by forcing electrons to tunnel between two magnetic materials through an insulator, a process forbidden by classical physics, we build non-volatile memories. In the same way, by using light and the energy gap of a semiconductor, we create electron-hole pairs in a solar cell through the photovoltaic effect, a phenomenon that also relies on quantum mechanics. However, it is only in the last 20 years that we have gained understanding of important geometrical and topological properties encoded in the electrons’ wavefunction, that have a profound impact on the macroscopic behavior of a material.

The term quantum materials spans to a large portfolio of compounds, where electrons are under the influence of many competing effects, such as electronic correlations, crystal field effects, topology, spin-orbit coupling, and more. In this talk, I will discuss the eventful life of electrons in these materials and how these interactions lead to new phases of matter.