Title: “Correlation, disorder, incommensuration, topology: Strange beauty of 2D moire systems”
Speaker: Sankar Das Sarma, University of Maryland
Abstract: I will discuss the physics of many fascinating phenomena being discovered in 2D twisted heterostructures, focusing on graphene and dichalcogenide systems. There are many things that we, certainly I, do not understand except that there is general agreement on electron-electron interactions being the dominant driving force behind much of the observed physics: superconductivity, conductor-insulator transition, magnetism, strange metallicity with very high resistivity… I will discuss some of our theories, emphasizing many aspects which remain mysterious. My personal goal is to develop a minimal model which may capture the whole physics of these moire systems, but I am not sure that this can be done, it is certainly not going to be easy. My hope is that we will develop some consensus unlike the cuprates, which are also two-dimensional (in a somewhat different sense from these moire systems), where a theoretical consensus still eludes the community after more than 30 years of intensive research.