Exact ground states of spin-2 chains

Abstract

We use the matrix product approach to construct all optimum ground states of general anisotropic spin-2 chains with nearest neighbour interactions and common symmetries. These states are exact ground states of the model and their properties depend on up to three parameters. We find three different antiferromagnetic Haldane phases, one weak antiferromagnetic and one weak ferromagnetic phase. The antiferromagnetic phases can be described as spin liquids with exponentially decaying correlation functions. The variety of phases found with the matrix product ansatz also gives insight into the behaviour of spin chains with arbitrary higher spins.

7 pages, 2 figures, to be published in europhysics letters, uses epl.cls

Cited by in corpus (11)

• The matrix product representations for all valence bond states
• Quantum Phase Transitions and Matrix Product States in Spin Ladders
• Digital Discovery of 100 diverse Quantum Experiments with PyTheus
• Exact ground states of quantum spin-2 models on the hexagonal lattice
• A complete characterization of the spectrum of the Kitaev model on spin ladders
• Exact ground states for coupled spin trimers
• Exact dimer ground states for a continuous family of quantum spin chains
• The Asymmetric Valence-Bond-Solid States in Quantum Spin Chains: The Difference Between Odd and Even Spins
• Exact symmetry breaking ground states for quantum spin chains
• A classification of spin 1/2 matrix product states with two dimensional auxiliary matrices
• A new family of matrix product states with Dzyaloshinski-Moriya interactions