PIRSA:16040106

Video URL

https://pirsa.org/16040106

Spin liquids on kagome lattice and symmetry protected topological phase

He, Y. (2016). Spin liquids on kagome lattice and symmetry protected topological phase. Perimeter Institute for Theoretical Physics. https://pirsa.org/16040106

He, Yin-Chen. Spin liquids on kagome lattice and symmetry protected topological phase. Perimeter Institute for Theoretical Physics, Apr. 19, 2016, https://pirsa.org/16040106 

          @misc{ scivideos_PIRSA:16040106,
            doi = {10.48660/16040106},
            url = {https://pirsa.org/16040106},
            author = {He, Yin-Chen},
            keywords = {Quantum Matter},
            language = {en},
            title = {Spin liquids on kagome lattice and symmetry protected topological phase},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2016},
            month = {apr},
            note = {PIRSA:16040106 see, \url{https://scivideos.org/index.php/pirsa/16040106}}
          }

Yin-Chen He Perimeter Institute for Theoretical Physics

Talk numberPIRSA:16040106
DOI10.48660/16040106
Source RepositoryPIRSA
Collection
Talk Type Scientific Series
Subject

Abstract

In my talk I will introduce the spin liquid phases that occur in kagome antiferromagnets, and discuss their physical origin that are closely related with the newly discovered symmetry protected topological phase (SPT). I will first present our numerical (DMRG) study on the kagome XXZ spin model that exhibits two distinct spin liquid phases, namely the chiral spin liquid and the kagome spin liquid (the groundstate of the nearest neighbor kagome Heisenberg model). Both phases extend from the extreme easy-axis limit, through

SU(2) symmetric point, to the pure easy-plane limit. The two phases are separated by a continuous phase transition. Motivated by these numerical results, I will then focus on the easy-axis kagome spin system, and reformulate it as a lattice gauge model. Such formulation enables us to achieve a controlled theoretical description for the spin liquid phases. We then show that the chiral spin liquid is indeed a gauged U(1) SPT phase. On the other hand, we also propose that the kagome spin liquid is a critical spin liquid phase, which can be considered as a gauged deconfined critical point between a SPT and a superfluid phase.