Physics and Astronomy Colloquium – Richard Scalettar
August 27 @ 4:00 pm - 5:30 pm
UNC-CH Physics and Astronomy Colloquium
Richard Scalettar, UC Davis
“The Hubbard Model: From solids to cold atoms and back again”
Over the last half-century, the Hubbard Hamiltonian has been extensively studied and applied to some of the most fundamental problems in solid state physics. I will first discuss how it provides simple physical pictures which lead to a qualitative understanding of the origin of magnetism and insulating behavior in transition metal oxides, and even Cooper pairing and density inhomogeneities in high temperature superconductors. Unfortunately, exact solution (either analytic or numeric) of the Hubbard model is not possible except in special limits. In an effort to understand its properties better, attempts have been made over the last decade to emulate the Hubbard model with ultracold atoms. A description of these experiments, and their successes and failures, will be presented. Finally, in just the least year or so, a new proposal has emerged to emulate the Hubbard Hamiltonian using engineered defects in thin silicon sheets. This suggestion returns the model to its solid state roots, and may offer at last a quantitatively accurate revelation of its mysteries.