The various embodiments described herein include methods, devices, and systems for fabricating and performing operations on magnetic memory devices. In one aspect, a magnetic memory device includes: (1) a reference magnetic layer configured to have a first current threshold corresponding to a spin current level required to change a magnetic polarization of the reference magnetic layer; (2) a composite magnetic layer comprising a plurality of non-magnetic layers and a plurality of magnetic layers including a storage layer; and (3) a non-magnetic spacer layer between the reference magnetic layer and the composite magnetic layer; where the composite magnetic layer is configured such that the second current threshold is lowered, without decreasing thermal stability of the magnetic memory device, by spin current and/or coupling fields between adjacent magnetic layers of the plurality of magnetic layers.