Abstract: A spin polarization enhancement artificial (SPEA) magnet comprises combinations of positive spin asymmetry interfaces and inverse spin asymmetry interfaces arranged antiferromagnetically such that current passed through the SPEA magnet has enhanced spin polarization. The SPEA magnet additionally may combine bulk material properties of electron scattering to either supplement or replace the interfacial spin differentiation. A basic functional unit of the SPEA magnet includes two ferromagnetic layers separated by two spacer layers. Each spacer forms an interface such that adjacent ferromagnetic layers produce different spin symmetry. Antiferromagnetic arrangement of adjacent ferromagnetic layers coordinates the different spin symmetries such that a single spin state is selected and also provides additional stabilization to the SPEA magnet.

Abstract: An apparatus for swaging an end of a tubular (22) is described as comprising a swaging head (17) for providing the swage to the end of the tubular (22). The swaging head (17) has two or more formations (22A, 22B) provided thereon to permit swaging of differing diameters of tubular ends. The apparatus may comprise a stop plate (5, 9) for abutment against the other end of a tubular (22) where the swaging head (17) and the stop plate (5, 9) are movably coupled to one another. The apparatus may have a clamping device (4) for clamping the tubular (22), where the clamping device is split into at least three part-circular clamping segments (30) which clamp around the outer circumference of the tubular to permit it to be swaged. The clamping device (4) may have a plurality of teeth (35) for gripping the outer surface of the tubular (22), and a plurality of grooves 36 formed between the teeth (35).