A new family of models with exact ground states connecting smoothly the S=1/2 dimer and S=1 Haldane phases of 1D spin chains

Abstract

We investigate the isotropic two-leg S=1/2 ladder with general bilinear and biquadratic exchange interactions between spins on neighboring rungs, and determine the Hamiltonians which have a matrix product wavefunction as exact ground state. We demonstrate that a smooth change of parameters leads one from the S=1/2 dimer and Majumdar-Ghosh chains to the S=1 chain with biquadratic exchange. This proves that these model systems are in the same phase. We also present a new set of models of frustrated S=1/2 spin chains (including only bilinear NN and NNN interactions) whose ground states can be found exactly.

4 pages, RevTeX, uses psfig.sty, submitted to Phys. Rev. Lett

Cited by in corpus (22)

• One-Dimensional Magnetism
• Effects of biquadratic exchange on the spectrum of elementary excitations in spin ladders
• Phase Transitions Between Topologically Distinct Gapped Phases in Isotropic Spin Ladders
• Non-Haldane Spin Liquid Models with Exact Ground States
• Finitely Correlated Generalized Spin Ladders
• String order and adiabatic continuity of Haldane chains and band insulators
• Topological Order, Dimerization, and Spinon Deconfinement in Frustrated Spin Ladders
• A matrix product solution for a nonequilibrium steady state of an XX chain
• Phase diagrams of spin ladders with ferromagnetic legs
• $S=1/2$ Chain-Boundary Excitations in the Haldane Phase of 1D $S=1$ Systems
• An Exactly Solvable Model of Generalized Spin Ladder
• Residual entropy and spin gap in a one-dimensional analog of the pyrochlore antiferromagnet
• Elementary excitations in the gapped phase of a frustrated S=1/2 spin ladder: from spinons to the Haldane triplet
• Electronic Ladders with SO(5) Symmetry: Phase Diagrams and Correlations at half-filling
• Exact Results for the Bipartite Entanglement Entropy of the AKLT spin-1 chain
• Highest weight state description of the isotropic spin-1 chain
• Nonlinear sigma model study of a frustrated spin ladder
• Models of impurities in valence bond spin chains and ladders
• A general CFT model for antiferromagnetic spin-1/2 ladders with Mobius boundary conditions
• Exact singlet bond ground states for electronic models
• Exact plaquette singlet phases in an orthogonal-plaquette model
• Reconfigurable dissipative entanglement between many spin ensembles: from robust quantum sensing to many-body state engineering