title: Ground states of the SU(N) Heisenberg model.
abstract: The SU(N) Heisenberg model with various single-row representations is investigated by quantum Monte Carlo simulations. While the zero-temperature phase boundary agrees qualitatively with the theoretical predictions based on the 1/N expansion, some unexpected features are also observed. For N> or =5 with the fundamental representation, for example, it is suggested that the ground states possess exact or approximate U(1) degeneracy. In addition, for the representation of Young tableau with more than one column, the ground state shows no valence-bond-solid order even at N greater than the threshold value.
authors.affiliation: Institute for Solid State Physics, University of Tokyo, Kashiwa 5-1-5, Chiba 277-8581, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Kawashima
authors.forename: Yuta
authors.initials: Y
authors.lastname: Tanabe