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Symmetry adapted finite-cluster solver for quantum Heisenberg model in two-dimensions: a real-space renormalization approach

V. E. Sinitsyn·I. G. Bostrem·A. S. Ovchinnikov
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Abstract

We present a quantum cluster solver for spin-$S$ Heisenberg model on a two-dimensional lattice. The formalism is based on the real-space renormalization procedure and uses the lattice point group-theoretical analysis and nonabelian SU(2) spin symmetry technique. The exact diagonalization procedure is used twice at each renormalization group step. The method is applied to the spin-half antiferromagnet on a square lattice and a calculation of local observables is demonstrated. A symmetry based truncation procedure is suggested and verified numerically.

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V. E. Sinitsyn, I. G. Bostrem, A. S. Ovchinnikov. 2006-12-14. Symmetry adapted finite-cluster solver for quantum Heisenberg model in two-dimensions: a real-space renormalization approach. https://doi.org/10.1088/1751-8113%2F40%2F4%2F006

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