Intense research efforts are currently aimed at establishing a fundamental link between spintronics, molecular electronics and quantum computation. Novel materials could usher a true revolution in this area, and magnetic graphene nanoribbons, in particular, have attracted impressive theoretical attention, but their creation had proved elusive, until very recently. The ERC action MMGNRs has tested the theoretical predictions and the untapped applicative potential of graphene nanoribbons. By creating graphene nanoribbons from a molecular bottom-up synthetic procedure, instead of the usual methods of cutting out graphene nanoribbons from large sheets, or randomly placing magnetic molecules on graphene surfaces, we could tune their properties as never before. We could inject a spin density is injected into the graphene backbone, and study edge effects with unprecedented accuracy. Via low-temperature transport and pulsed electron-paramagnetic-resonance spectroscopy MMGNRs could reveal the classical and quantum magnetic properties of the graphene spin states. MMGNRs thus demonstrated that our theories of graphene magnetic states are indeed right, that we can use the resulting graphene magnetic states to perform quantum logic operations, and that it is possible to push the quantum effects to high temperatures, integrating these systems into electronic nanodevices. In the previous periods several questions had already found an answer from the results of the project:
1- that it is possible to create graphene nanosystems with long quantum coherence times
2- that they can be addressed electronically and electronic logic devices can be created out of them
Nonetheless, at the beginning of the final part of the project, there remained important questions of scientific and applicative importance:
3- can that the magnetic and optical states be detected? and how?
4- can the interesting quantum properties be retained at high temperatures? Is this thus useful for practical devices in room-temperature electronics?
5- can topological effects be used to tune the quantum properties as desired?
Our results in this final period have provided a positive answer to all of these remaining questions. In particular, it was found that the quantum properties are, surprisingly, retained up to room temperature, so that they can be exploited in electronic devices that are commercially exploitable. At the societal level, this means that we can produce nanoelectronic elements, made of graphene nanoribbons, that work as logic units at a fraction of the energy cost of normal logic devices. Moreover, the quantumn effects also allow harvesting the residual heat from other components, transforming it into an electric voltage that can be "recycled" within the circuitry itself. We plan to exploit these results, together with large companies, to develop carbon-based logic devices that work at a fraction of the energy consumption. Nowadays ca 20% of our energy consumption goes into powering IT and logic devices, so that being able to cut this consumption down is a goal of primary societal interest.
The action thus met the original objectives, and some of the observations exceeded our expectations, showing unexpected behaviours that are not only interesting scientifically, but also and extremely promising for applications, and a new field is thuis raising, rapidly gaining attention all over the world.
