Linear - Algebraic Results Associated with Antiferromagnetic Heisenberg Chains
نویسندگان
چکیده
This paper analyses the 3 × 3 self-adjoint matrix HN = N−1 ∑ j=1 S (j) x S (j+1) x + S (j) y S (j+1) y + S (j) z S (j+1) z , the Hamiltonian of a spin-1, one-dimensional, Heisenberg antiferromagnet. Various results are obtained, including alternative representations of HN , families of operators commuting with HN , a complete description of the spin-0 subspace (which includes all oneand two-dimensional eigenspaces of HN ), and a proof that HN must have an eigenvalue smaller than − 4 3 (N − 1).
منابع مشابه
Linear-algebraic Results Associated with Antiferromagnetic Heisenberg Chains* Abstract. This Paper Analyses the 3 N 3 N Self-adjoint Matrix H N =
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