Real-Space Renormalization-Group Analysisof the S=2 Antiferromagnetic Heisenberg Chain

Abstract

The S=2 antiferromagnetic Heisenberg open chain is analyzed with the real-space numerical renormalization-group method improved by White. The low-lying spectrum and the one-point function are evaluated to show the degeneracy and the boundary effect on the ground state. Generalized string correlation functions were calculated for θ =π and θ =π\frasl2. The θ =π\frasl2 string correlation is found to indicate the long-range hidden order of the ground state. These results are quite consistent with the S=2 VBS argument.