Condensed Matter Physics Seminar: Wavefunctions of symmetry protected topological phases and conformal field theories

Abstract:

In has long been known that conformal field theories (CFTs) in 2D and topological phases in 2+1D are closely related topics. The correspondence between them allows one to write fractional quantum Hall wavefunctions as many operator correlators in a CFT, thereby providing strong analytical tools to study the bulk and edge excitations of these phases. Whether a similar relation holds between symmetry protected topological phases (SPTs) and CFTs is an open question. In this talk, I'll consider several known lattice wavefunctions of integer SPTs and show how a correspondence with CFTs, similar but not identical to the one above, emerges at large scales. In some cases, the resulting large scale wavefunction takes a Laughlin-like form which includes the flux attachment, hidden order, and plasma structures. Other potential benefits of this approach, both for the study of exotic SPTs as well as for less understood CFTs will also be discussed.
 

Seminar Organizer: Prof. Shimshon Barad