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Physical review. B, Condensed matter

Phase diagrams of the quantum transverse spin- 32 Ising system with bimodal random field

Erhan Albayrak

Published Mar 22, 2002• 18 citations
Publisher

Abstract

The bimodal random field quantum spin-$\frac{3}{2}$ Ising system is investigated by combining the pair approximation with the discretized path-integral representation. The second-order phase transition lines, and tricritical points are obtained for the bimodal random field distribution. Reentrant phase transitions, which may be caused by the competition between quantum effects and randomness, are observed. The phase diagrams with respect to the random field and the second-order phase transition temperature, i.e., (H, T) plane, are studied extensively for given values of the transverse field G and the coordination number z.

DOI
10.1103/physrevb.65.134429

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