JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, cilt.355, ss.235-239, 2014 (SCI-Expanded)
In this paper we study the quantum spin-1/2 anisotropic Heisenberg antiferromagnet model in the presence of a Dzyaloshinskii-Moriya interaction (D) and a uniform longitudinal (H) magnetic held. Using the effective-held theory with a finite cluster N=2 spin (EFT-2) we calculate the phase diagrams in the H - T and D - T planes on a simple cubic lattice (z=6). We have only observed second order phase transitions for values between Delta is an element of [0, 1], where the cases were analysed: [sing (Delta = 1), anisotropic Heisenberg (Delta = 0.6) and isotropic Heisenberg (Delta = 0). Crown Copyright (C) 2014 Published by Elsevier B.V. All rights reserved.