A new method to solve the S=1/2 Heisenberg spin chain

G.R.W. Quispel, Hans W. Capel

Nian Lin, Zurong Yu, 同济大学物理系,上海200092

We present a new approach which is completely based on the permutation group theory to solve the eigenvalue problem of the S = 1/2 Heisenberg finite-chain with free-ends boundary. All of the eigenvalues and the corresponding eigenstates are obtained. The properties of the ground state and the low-lying excited states of the antiferromagnetic chain are examined.

Gábor Fáth, Paolo Maria Santini, Zbigniew Domański +1 more

Ian Yu

We present a new approach which is completely based on the permutation group theory to solve the eigenvalue problem of the S = 1/2 Heisenberg finite-chain with free-ends boundary. All of the eigenvalues and the corresponding eigenstates are obtained. The properties of the ground state and the low-lying excited states of the antiferromagnetic chain are examined.

Carlo Heissenberg, Augusto Sagnotti

Pengcheng Lu, Yi Qiao, Junpeng Cao +3 more

Abstract A new nonlinear integral equation (NLIE) describing the thermodynamics of the Heisenberg spin chain is derived based on the t − W relation of the quantum transfer matrices. The free energy of the system in a magnetic field is thus obtained by solving the NLIE. This method can be generalized to other lattice quantum integrable models. Taking the SU(3)-invariant quantum spin chain as an example, we construct the corre- sponding NLIEs and compute the free energy. The present results coincide exactly with those obtained via other methods previously.