title: Quantum critical spin-2 chain with emergent SU(3) symmetry.
abstract: We study the quantum critical phase of an SU(2) symmetric spin-2 chain obtained from spin-2 bosons in a one-dimensional lattice. We obtain the scaling of the finite-size energies and entanglement entropy by exact diagonalization and density-matrix renormalization group methods. From the numerical results of the energy spectra, central charge, and scaling dimension we identify the conformal field theory describing the whole critical phase to be the SU(3)_{1} Wess-Zumino-Witten model. We find that, while the Hamiltonian is only SU(2) invariant, in this critical phase there is an emergent SU(3) symmetry in the thermodynamic limit.
authors.affiliation: Department of Physics and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan.|Physics Division, National Center for Theoretical Sciences, Hsinchu 30013, Taiwan.
authors.forename: Pochung
authors.initials: P
authors.lastname: Chen
authors.affiliation: Department of Physics and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Zhi-Long
authors.initials: ZL
authors.lastname: Xue
authors.affiliation: Centre for Engineered Quantum Systems, The University of Queensland, Brisbane, Queensland 4072, Australia.
authors.forename: I P
authors.initials: IP
authors.lastname: McCulloch
authors.affiliation: Physics Division, National Center for Theoretical Sciences, Hsinchu 30013, Taiwan.|Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan.
authors.forename: Ming-Chiang
authors.initials: MC
authors.lastname: Chung
authors.affiliation: Institute of Physics and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: Chao-Chun
authors.initials: CC
authors.lastname: Huang
authors.affiliation: Institute of Physics and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: S-K
authors.initials: SK
authors.lastname: Yip