Abstract

We study bosonic symmetry-protected topological (SPT) phases with C-2 rotational symmetry in four spatial dimensions which is not captured by the group cohomology classification. By using the topological crystal approach, we show that the topological crystalline state of this SPT phase is given by placing an E-8 state on the two-dimensional rotational invariant plane, which provides a simple physical picture of this phase. Based on this understanding, we show that a variant of QED in four dimensions (QED(4)) with charge-1 and charge-3 Dirac fermions is a field theoretical description of the three-dimensional boundary. We also discuss the connection to a symmetric gapped boundary with topological order and its anomalous signature.

Publication Details
Author
Publication Type
Journal Article
Year of Publication
2020
Volume
2
DOI
10.1103/PhysRevResearch.2.033236
Journal
Physical Review Research
Contributors
Groups