The Landau-Ginzburg-Wilson theory of phase transitions has been enormously successful in capturing the physics of ordered-to-disordered phase transitions. It is possible to have a direct, second-order transition between two ordered phases with different symmetries, but this is beyond the LGW paradigm. This was first demonstrated on the square lattice Heisenberg antiferromagnet, and the critical point is filled with interesting structure. In this talk, I will describe a new type of deconfined quantum criticality on the triangular lattice. This new critical point captures the complicated "intertwinement" of VBS and Neel order, and its RG properties are studied. I will also discuss connections to SPT (symmetry protected topological) phases and the LSM theorem.
Reference: https://arxiv.org/abs/1710.04668
Faculty Host:Yuanming Lu