Some features of the phase diagram of the square lattice (1989)

Content Provider	CiteSeerX
Author	Read, N. Sachdev, Subir
Abstract	We study the properties of the nearest neighbor SU(N) antiferromagnet on a square lattice as a function of N and the number of rows (m) and columns (nc) in the Young tableau of the SU(N) representation on the A sublattice; the sites of the B sublattice have the conjugate representation (the familiar Heisenberg antiferromagnet has N = 2, m = 1 and nc = 2S). We study the global phase diagram in the (N,m, nc) space using 1/N expansions; in particular: (i) for N large with m proportional to N and nc arbitrary, we find spin-Peierls (dimerized) ground states with short-range spin correlations;(ii) with m = 1, the model is shown to be equivalent, at order 1/N, to a generalized quantum dimer model. We discuss the relationship of these results to the SU(N) generalization of recent arguments by Haldane on the effect of ‘hedgehog ’ point singularities in the space-time spin configuration. As an intermediate step in our calculation, we present a simple new derivation of the coherent state path integral representation of SU(N) spin models.
File Format	PDF
Journal	SU(N ) antiferromagnet, Nucl. Phys. B
Language	English
Publisher Date	1989-01-01
Access Restriction	Open
Subject Keyword	Square Lattice Phase Diagram Simple New Derivation Intermediate Step Neighbor Su Ground State Global Phase Diagram Spin Model Young Tableau Familiar Heisenberg Antiferromagnet Short-range Spin Correlation Conjugate Representation Quantum Dimer Model Recent Argument Space-time Spin Configuration Coherent State Path Integral Representation Hedgehog Point Singularity
Content Type	Text
Resource Type	Article