In (Eu,Gd)Te semiconductor alloys a well known antiferromagnetic semiconductor compound EuTe is transformed into n-type ferromagnetic alloy. This effect is driven by the RKKY interaction via conducting electrons created due to substitution of Gd3+ for Eu2+ ions. It is expected that due to the high degree of electron spin polarization (Eu,Gd)Te can be exploited in new semiconductor spintronic heterostructures as a model injector of spin-polarized carriers. The (Eu,Gd)Te monocrystalline layers with Gd content up to 5 at. % were grown by MBE on BaF2 (111) substrates with either PbTe or EuTe buffer layers. The measurements of magnetic susceptibility and magnetization revealed that the ferromagnetic transition with the Curie temperature TC=11- 15 K is observed in (Eu,Gd)Te layers with n-type metallic conductivity. An analysis of the magnetization of (Eu,Gd)Te was carried out in a broad range of magnetic fields applied along various crystal directions both in- and out-of layer plane. It revealed, in particular, that a rapid low field ferromagnetic response of (Eu,Gd)Te layer is followed by a paramagnetic-like further increase towards the full saturatio
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This paper provides the results of exchange-bias simulation of a single ferromagnetic (FM) layer coupled to a quenched antiferromagnetic (AFM) region using a Random Field Ising Model (RFIM) approach. Using the RFIM algorithm the shapes of exchange-biased hysteresis loops, featuring perpendicular magnetic anisotropies, were obtained. Providing a possible explanation of this effect the recognized stable part of an interface magnetisation represented by unreversed spins at the interface was evidently simulated. Obtained results are consistent with the Domain State Model (DSM) model, where a part of the AFM interface magnetisation is stable during hysteresis loop creation
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