title: Fate of CPN-1 fixed points with q monopoles.
abstract: We present an extensive quantum Monte Carlo study of the Néel to valence-bond solid (VBS) phase transition on rectangular- and honeycomb-lattice SU(N) antiferromagnets in sign-problem-free models. We find that in contrast to the honeycomb lattice and previously studied square-lattice systems, on the rectangular lattice for small N, a first-order Néel-VBS transition is realized. On increasing N≥4, we observe that the transition becomes continuous and with the same universal exponents as found on the honeycomb and square lattices (studied here for N=5, 7, 10), providing strong support for a deconfined quantum critical point. Combining our new results with previous numerical and analytical studies, we present a general phase diagram of the stability of CPN-1 fixed points with q monopoles.
authors.affiliation: Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506-0055, USA.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Block
authors.forename: Roger G
authors.initials: RG
authors.lastname: Melko
authors.forename: Ribhu K
authors.initials: RK
authors.lastname: Kaul