1998/07/31 by S. Albeverio, S. M. Fei, Shuangwen Fei +2 · 32 citations
Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Bethe ansatz #Coupling constant #Ground state #Hamiltonian (control theory) #Heisenberg model #Integrable system #Invariant (physics) #Mathematical physics #Mathematics #Physics #Physics of Superconductivity and Magnetism #Quantum #Quantum many-body systems #Quantum mechanics #Spin model #Thirring model #cond-mat
paper · pdf · doi:10.1209/epl/i1999-00397-8
published in Europhysics Letters (EPL) 47(3), 364-370 (Institute of Physics)
openalex publication_date 1999/08/01 · arxiv created 1999/08/18 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
A detailed study of an S = ½ spin ladder model is given. The ladder consists of plaquettes formed by nearest-neighbor rungs with all possible SU (2)-invariant interactions. For properly chosen coupling constants, the model is shown to be integrable in the sense that the quantum Yang-Baxter equation holds and one has an infinite number of conserved quantities. The R -matrix and L -operator associated with the model Hamiltonian are given in a limiting case. It is shown that after a simple transformation, the model can be solved via a Bethe ansatz. The phase diagram of the ground state is exactly derived using the Bethe ansatz equation.