A material layer stack for a pSTTM device includes a fixed magnetic layer, a tunnel barrier disposed above the fixed magnetic layer and a free layer disposed on the tunnel barrier. The free layer further includes a stack of bilayers where an uppermost bilayer is capped by a magnetic layer including iron and where each of the bilayers in the free layer includes a non-magnetic layer such as Tungsten, Molybdenum disposed on the magnetic layer. In an embodiment, the non-magnetic layers have a combined thickness that is less than 15% of a combined thickness of the magnetic layers in the stack of bilayers. A stack of bilayers including non-magnetic layers in the free layer can reduce the saturation magnetization of the material layer stack for the pSTTM device and subsequently increase the perpendicular magnetic anisotropy.