Series study of the One-dimensional S-T Spin-Orbital Model

Abstract

We use perturbative series expansions about a staggered dimerized ground state to compute the ground state energy, triplet excitation spectra and spectral weight for a one-dimensional model in which each site has an $S=\case 1/2$ spin ${\mathbf{S}}_i$ and a pseudospin ${\mathbf{T}}_i$, representing a doubly degenerate orbital. An explicit dimerization is introduced to allow study of the confinement of spinon excitations. The elementary triplet represents a bound state of two spinons, and is stable over much of the Brillouine zone. A special line is found in the gapped spin-liquid phase, on which the triplet excitation is dispersionless. The formation of triplet bound states is also investigated.

9 pages, 9 figures

Cited by in corpus (8)

• High Order Perturbation Theory for Spectral Densities of Multi-Particle Excitations: S=1/2 Two-Leg Heisenberg Ladder
• Entanglement Entropy and Spectra of the One-dimensional Kugel-Khomskii Model
• Spin-Orbital Entanglement and Phase Diagram of Spin-orbital Chain with $SU(2)\times SU(2)$ Symmetry
• How spin-orbital entanglement depends on the spin-orbit coupling in a Mott insulator
• Thermodynamics of a one-dimensional S=1/2 spin-orbital model
• SU(4) Spin-Orbital Two-Leg Ladder, Square and Triangle Lattices
• Spin and orbital valence bond solids in a one-dimensional spin-orbital system: Schwinger boson mean field theory
• Spin-orbital gapped phase with least symmetry breaking in the one-dimensional symmetrically coupled spin-orbital model