Condensed Matter Seminar "Computing electron correlation effects: an auxiliary-field perspective"

Understanding the properties of strongly interacting quantum matter remains a grand challenge in physical sciences. Computation has an integral role to play in tackling this challenge. I will give an introduction to the fundamental issues facing accurate and predictive computations of quantum systems, and then describe recent progress in combining field-theory and Monte Carlo simulations for computations in many-fermion systems. This framework can be used for ab initio materials simulations as well as lattice model studies. As an example of the former, results will be presented on the binding and magnetic properties of Cobalt adatom on graphene, a setup that has drawn interest for possible spintronics applications. As an example of lattice model calculations, we determine ground-state properties of the Hubbard model, which is important in the context of high-Tc superconductivity and whose laboratory emulation is one of the major goals for optical lattice experiments.