we describe a cpp mtj mram element that utilizes transfer of spin angular momentum as a mechanism for changing the magnetic moment direction of a free layer . the device includes a tunneling barrier layer of mgo and a non - magnetic cpp layer of cu or cr and utilizes a novel synthetic free layer having three ferromagnetic layers mutually exchange coupled in pairwise configurations . the free layer comprises an inner ferromagnetic and two outer ferromagnetic layers , with the inner layer being ferromagnetically exchange coupled to one outer layer and anti - ferromagnetically exchange coupled to the other outer layer . the ferromagnetic coupling is very strong across an ultra - thin layer of ta , hf or zr of thickness preferably less than 0 . 4 nm .