CMSA Condensed Matter/Math Seminar: Symmetry enriched U(1) quantum spin liquids and beyond

I will present our characterization and classification of 3+1 dimensional U(1) quantum spin liquids (QSLs) enriched by symmetries. These QSLs are spin system described by a deconfined U(1) gauge theory at low energies, and we assume that the only gapless degree of freedom is the photon. I will mostly focus on the example where the symmetry includes SO(3) spin rotation and time reversal, from which I will summarize our general scheme for the characterization and classification. The characterization and classification are based on the properties of the matters coupled to the emergent U(1) gauge field, although they are gapped. I will also discuss some applications of the ideas developed here to topological phases protected by crystalline symmetries. In order to avoid potential misunderstanding due to the difference in the ideology and language between physicists with different background, I will give an overview of these differences at the beginning of the talk.

via Zoom Video Conferencing: https://harvard.zoom.us/s/977347126