|DATE||September 19 (Thu), 2019|
|INSTITUTE||California Institute of Technology|
|TITLE||The relation between free and interacting fermionic SPT phases|
Some symmetry-protected topological (SPT) phases of free fermions can be destabilized by turning on interactions; on the other hand, there are some SPT phases which are inherently interacting, with no free fermionic realization. In this talk, I will give a classification of free fermionic systems with arbitrary unitary on-site symmetry, extending the ten-fold way periodic table, and describe the relation between free and interacting phases within a given symmetry class. In spatial dimension zero and one, we will construct a general map telling us which interacting phase a given free fermionic phase corresponds to, and show that there are inherently interacting phases even in zero dimension.