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50nm thick nanogranular polycrystalline dysprosium thin films have been prepared via ultra-high vacuum DC sputtering on SiO2 and Si wafers. The maximum in-plane spontaneous magnetization at T = 4K was found to be MS4K = 3.28T for samples deposited on wafers heated to 350C with a Neel point of TN = 173K and a ferromagnetic transition at TC = 80K, measured via zero field cooled field cooled magnetization measurements, close to single crystal values. The slightly reduced magnetization is explained in the light of a metastable face centered cubic crystal phase which occurred at the seed interface and granularity related effects, that are still noticeably influential despite an in-plane magnetic easy axis. As deposited samples showed reduced magnetization of MS4K = 2.26T, however their ferromagnetic transition shifted to a much higher temperature of TC = 172K and the antiferromagnetic phase was completely suppressed probably as a result of strain., Comment: 16 pages, 3 figures

The search for materials or systems exhibiting a high magnetic saturation has been of longstanding importance. It has been suggested that increased saturation could be achieved by coupling a transition metal via a spacer to a rare earth. We report Gd/Cr/Fe70Co30 multilayer stacks and find reduced yet modulating magnetic moment as a function of Cr thickness. Through a micro structural analysis the lowered moment is indicated by the nucleation of the ultrathin Gd films into an fcc phase. We discuss the possible solution in terms of quasi-perfect lattice match seed material to promote growth of hcp Gd., Comment: 14 pages, 5 figures, submitted to Appl. Phys. Lett

There is renewed interest in rare-earth elements and gadolinium in particular for a range of studies in coupling physics and applications. However, it is still apparent that synthesis impacts understanding of the intrinsic magnetic properties of thin gadolinium films, particularly for thicknesses of topicality. We report studies on 50nm thick nanogranular polycrystalline gadolinium thin films on SiO2 wafers that demonstrate single-crystal like behavior. The maximum in-plane saturation magnetization at 4K was found to be 4{\pi}MS4K = (2.61{\pm}0.26)T with a coercivity of HC4K = (160{\pm}5)Oe. A maximum Curie point of TC = (293{\pm}2)K was measured via zero-field-cooled - field- cooled magnetization measurements in close agreement with values reported in bulk single crystals. Our measurements revealed magnetic transitions at T1 = (12{\pm}2)K (as deposited samples) and T2 = (22{\pm}2)K (depositions on heated substrates) possibly arising from the interaction of paramagnetic fcc grains with their ferromagnetic hcp counterparts., Comment: 14 pages, 3 figures, to be publ