2008/09/11 by Stephan Rachel, Martin Greiter · 1 citation
Materials Science · Physics and Astronomy · #Magnetism in coordination complexes #Physics of Superconductivity and Magnetism #Quantum many-body systems #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.78.134415
published as Phys. Rev. B 78, 134415 (2008) · 7 pages, 8 figures
arxiv created 2008/09/11 · openalex publication_date 2008/10/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present exact models for an antiferromagnetic S=1 spin chain describing trimerization as well as for an antiferromagnetic S=3/2 spin chain describing tetramerization. These models can be seen as generalizations of the Majumdar-Ghosh model. For both models, we provide a local Hamiltonian and its exact threefold or fourfold degenerate ground state wave functions, respectively. We numerically confirm the validity of both models using exact diagonalization and discuss the low-lying excitations.