题 目：Symmetry Protected Topological phases: model realization and numerical detection

报告人：刘正鑫 副研究员 (清华大学高等研究中心)

时  间：2014年9月10日（周三）上午10点；

地  点：中心教学楼610

ABSTRACT
Symmetry protected topological (SPT) phases are gapped phases that do not break any symmetry. SPT phases have nontrivial boundary excitations. For example, in 1+1D, nontrivial SPT phases protected by onsite symmetry have degenerate edge states; in 2+1D, the edge states are gapless if the symmetry is non-broken. Topological insulators are examples of fermionic SPT phases. SPT phases also exist in interacting bosonic systems. In this talk, I will discuss realization of 2+1D bosonic topological insulators protected by U(1) and time reversal symmetry. I will also show numerical evidence of U(1)*U(1) SPT order in a spin-1 wave function on Kagome lattice.