Abstract: A fundamentally new magnetic tunnel junction technology based on the use of magnetic nanoparticles is disclosed. The hard layer of the device is composed of the nanoparticles, while the junction insulating barrier is composed of a carbon-based coating on the nanoparticles. This device offers a markedly different approach of tunnel junction fabrication and offers many advantages over the prior art technology, which is based on the use of oxidized aluminum as the insulating barrier.