Magnetic behavior of the diluted antiferromagnet Mn0.39Zn0.61F2 at strong fields

The magnetic phase boundaries of the random-field Ising model (RFIM) system Mn 0.39 Zn 0 61F2 are determined using magnetization measurements, under finite DC applied fields (H). At low fields (H < 12 kOe), our results support a critical phase boundary, separating an ordered antiferromagnetic (AF) phase from the paramagnetic (P) one. For intermediate fields (12 < H < 18 kOe), the AF ordering coexists with a spin-flop (SF) clustering. For higher H, a spin-flop phase dominates the upper part of the (H,T) phase diagram.