Spin-3/2 models on the Cayley tree -- optimum ground state approach

H. Niggemann; J. Zittartz

doi:10.1007/s100510050904

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Spin-3/2 models on the Cayley tree -- optimum ground state approach

H. Niggemann·J. Zittartz

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Abstract

We present a class of optimum ground states for spin-3/2 models on the Cayley tree with coordination number 3. The interaction is restricted to nearest neighbours and contains 5 continuous parameters. For all values of these parameters the Hamiltonian has parity invariance, spin-flip invariance, and rotational symmetry in the xy-plane of spin space. The global ground states are constructed in terms of a 1-parametric vertex state model, which is a direct generalization of the well-known matrix product ground state approach. By using recursion relations and the transfer matrix technique we derive exact analytical expressions for local fluctuations and longitudinal and transversal two-point correlation functions.

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H. Niggemann, J. Zittartz. 1998-10-13. Spin-3/2 models on the Cayley tree -- optimum ground state approach. https://doi.org/10.1007/s100510050904

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