Complex phase diagrams are generic feature of quantum materials that display high temperature superconductivity. In addition to d-wave superconductivity (or other unconventional states), these phase diagrams typically include various forms of charge-ordered phases, including charge-density-waves and/or spin-density waves, and electronic nematic states. In most cases these phases have critical...
In this lecture I will concentrate on Majorana fermions as collective excitations and consider two examples related to my own research. The first is the 2-channel Kondo effect where Majorana zero mode emerges as a remnant of the overscreened impurity spin, and the other is the solvable model of 3D Kondo lattice where Majorana fermions of the spin liquid create bound states with conduction...
In this talk I will describe our recent progress in the development of Diagrammatic Monte Carlo techniques for the two-dimensional Fermi-Hubbard model. I will describe how correlations can lead to qualitative changes in the Fermi surface, or to a selective destruction of quasiparticle excitations near the antinodes in the pseudogap regime.
