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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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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.