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Heisenberg model in a random field: phase diagram and tricritical behavior

Douglas F. de Albuquerque·A. S. de Arruda
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Abstract

By using the differential operator technique and the effective field theory scheme we study the tricritical behavior of Heisenberg classical model of spin-1/2 in a random field. The phase diagram in the T-h plane on a square and simple cubic lattice for a cluster with two spins is obtained when the random field is bimodal distributed.

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Douglas F. de Albuquerque, A. S. de Arruda. 2002-03-19. Heisenberg model in a random field: phase diagram and tricritical behavior. https://doi.org/10.1016/s0378-4371(02)01204-9

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