Abstract The Ising model with transverse and longitudinal random fields, which have trimodal and bimodal distribution, respectively, for arbitrary spin (S), is investigated by combining the pair approximation with the discretized path integral representation (DPIR). The phase diagrams for S = 1, 1.5, and 2 are obtained, where some fascinating phenomena are observed.

physica status solidi (b)Jun 1, 19953 citations

Phase Diagram of a Quantum Transverse Spin‐1 Ising Model with Random Fields

Yu‐qiang Ma, Y. G., C. D. Gong

Abstract The quantum spin‐1 Ising system with random fields is investigated by combining the pair approximation with the discretized path‐integral representation. An analytical expression for the second‐order phase transition is derived for all symmetrical probability distributions of random fields, and phase diagrams for Gaussian and bimodal random fields are obtained numerically.

physica status solidi (b)Jul 1, 199311 citations