A modified double magnetic tunnel junction structure is provided which includes an amorphous spin diffusion layer (i.e., an amorphous non-magnetic, spin-conducting metallic layer) sandwiched between a magnetic free layer and a first tunnel barrier layer; the first tunnel barrier layer contacts a first magnetic reference layer. A second tunnel barrier layer is located on the magnetic free layer and a second magnetic reference layer is located on the second tunnel barrier layer. Such a modified double magnetic tunnel junction structure exhibits efficient switching (at a low current) and speedy readout (high tunnel magnetoresistance).