Several technological issues have to be faced to realize devices working at the single molecule level. One of the main challenges consists of defining methods to fabricate electrodes to make contact with single molecules. Here, we report the realization of novel spintronic devices made of a TbPc single molecule embedded between two nanometer-separated graphene electrodes, obtained by feedback-controlled electroburning. We demonstrate that this approach allows the realisation of devices working at low temperature. With these, we were able to characterize the magnetic exchange coupling between the electronic spin of the Tb magnetic core and the current passing through the molecular system in the Coulomb blockade regime, thus showing that the use of graphene is a promising way forward in addressing single molecules.

This manuscript discusses the difficulties with magnetic position and orientation (MPO) system design and proposes a general method for finding optimal layouts. The formalism introduces a system quality measure through state separation and reduces the question “How to design an MPO system?” to a global optimization problem. The latter is then solved by combining differential evolution algorithms with magnet shape variation based on analytical computations of the field. The proposed formalism is then applied to study possible realizations of continuous three-axis joystick motion tracking, realized with just a single magnet and a single 3D magnetic field sensor. The computations show that this is possible when a specific design condition is fulfilled and that large state separations as high as 1mT/∘ can be achieved under realistic conditions. Finally, a comparison to state-of-the-art design methods is drawn, computation accuracy is reviewed critically, and an experimental validation is presented.

In this work we report on fully operational sub-micrometric low voltage OFETs by using graphene as the sourcedrain electrodes pair and a high-κ ultra-thin dielectric in a local gate architecture. The impact of the graphene electrodes on the miniaturization of the organic devices has been assessed, with particular attention to the influence of the contact resistances as well as the parasitic overlap gate capacitance on the device bandwidth. By the use of a modified Transmission-Line-Method, contact resistances have been analyzed as function of the applied voltages, revealing characteristic functional trends that follow the doping state of graphene electrodes. Through impedance spectroscopy of the electrodes, cut-off frequencies as high as 10 5 Hz have been estimated, highlighting the peculiar role of quantum capacitance of graphene in such architectures.

Graphene nanodevices, such as ultra-narrow constrictions and nanometer-spaced gaps, are emerging as appealing candidates for various applications, ranging from advanced quantum devices to single-molecule junctions and even DNA sequencing. Here, we present the realization and characterization of nanometer-sized gaps in suspended few-layer graphene devices via feedback-controlled electroburning at room temperature. By analyzing the electrical behavior after the electroburning process, we identify two distinct regimes for the resulting devices, deriving a simple yet effective quantitative criterion to determine the complete opening of the nanogaps.