TANMS

(a) Transmission electron microscope (TEM) image of FePd nanocrystals with an average diameter of 5 nm. (b) Schematic diagram of stacks used to test the voltage dependence of magnetization in FePd nanocrystals. FePd nanocrystals (yellow) are deposited onto an MgO substrate and then coated in Ta to prevent aggregation and oxidation. The stacks are then thermally annealed in the presence of a magnetic field to orient the spins (arrows) normal to the substrate, creating the perpendicular magnetic anisotropy (PMA) required in devices. (c) Example magnetic hysteresis loops demonstrating PMA in an FePd nanocrystal test structure. The difference between the out-of-plane and in-plane magnetization curves is a measure of the anisotropy in the system (i.e., a large area between the two loops signifies the desired high PMA). (d) Schematic diagram of an example 2x2 bit array with magnetic tunnel junction (MTJ) bits (purple and orange cylinders), as would be seen in a hypothetical commercial device. The FePd nanocrystals would be the top, free-layer component (orange) of the MTJ.

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