Embodiments of the invention implement MEJs having improved read-write characteristics. In one embodiment, an MEJ includes: ferromagnetic fixed and free layers, a dielectric layer interposed between the ferromagnetic layers, and an additional dielectric layer proximate the free layer, where the fixed layer is magnetically polarized in a first direction, where the free layer has a first easy axis that is aligned with the first direction, and where the MEJ is configured such that when subject to a potential difference, the magnetic anisotropy of the free layer is altered such that the relative strength of the magnetic anisotropy along a second easy axis that is orthogonal to the first easy axis, compared to the strength of the magnetic anisotropy along the first easy axis, is magnified during the application of the potential difference, where the extent of the magnification is enhanced by the presence of the additional layer.