School of Physics, Condensed Matter Seminar| Dr. Wladimir Benalcazar | Emory University, Atlanta GA

Chern insulators present an obstruction to the construction of exponentially-localized Wannier functions; i.e., they lack a so-called “Wannier representation.” In this talk, I will address one of the outstanding questions in topological band theory: whether polarization and its boundary charge, which are well-defined on crystalline insulators having a Wannier representation, are well-defined in Chern insulators. I will show how, by recognizing a subtlety in the bulk-boundary correspondence of multipole moments, it is possible to describe charge accumulation in Chern insulators as arising from a response to polarization.