Researchers from Europe developed a graphene-based device that can detect magnetic fields with a record sensitivity (down to the stray field of few magnetic molecules, better than the previous record of sensitivity by a factor of 100). The graphene was used like a spider web to chemically 'trap' the molecules and detect their magnetization at the same time. This new development may enable ultra-high density Spintronics memory and molecular sensors.

This device was built by depositing magnetic molecules on a graphene sheet. The molecules were synthesized so that they are suitable to graft the graphene lattice. The electrical measurements were performed at very low temperature (to limit the noise). The new device works pretty much like a spin valve, only it's much smaller.

The reseach has been performed by the S3 Center of Istituto Nanoscienze-Cnr, the Insitut Néel - CNRS, and the Karlsruhe Institute of Technology.