Memristors are one of the most promising candidates for future information and communications technology (ICT) architectures. Two experimental proofs of concept are presented based on the intermixing of spintronic and memristive effects into a single device, a magnetically enhanced memristor (MEM). By exploiting the interaction between the memristance and the giant magnetoresistance (GMR), a universal implication (IMP) logic gate based on a single MEM device is realized.

Large area van der Waals (vdW) thin films are assembled materials consisting of a network of randomly stacked nanosheets. The multiscale structure and the twodimensional (2D) nature of the building block mean that interfaces naturally play a crucial role in the charge transport of such thin films. While single or few stacked nanosheets (i.e., vdW heterostructures) have been the subject of intensive works, little is known about how charges travel through multilayered, more disordered networks. Here, we report a comprehensive study of a prototypical system given by networks of randomly stacked reduced graphene oxide 2D nanosheets, whose chemical and geometrical properties can be controlled independently, permitting to explore percolated networks ranging from a single nanosheet to some billions with roomtemperature resistivity spanning from 10 −5 to 10 −1 Ω•m. We systematically observe a clear transition between two different regimes at a critical temperature T*: Efros−Shklovskii variable-range hopping (ES-VRH) below T* and power law behavior above. First, we demonstrate that the two regimes are strongly correlated with each other, both depending on the charge localization length ξ, calculated by the ES-VRH model, which corresponds to the characteristic size of overlapping sp 2 domains belonging to different nanosheets. Thus, we propose a microscopic model describing the charge transport as a geometrical phase transition, given by the metal−insulator transition associated with the percolation of quasi-one-dimensional nanofillers with length ξ, showing that the charge transport behavior of the networks is valid for all geometries and defects of the nanosheets, ultimately suggesting a generalized description on vdW and disordered thin films.

We report a systematic study on charge transport properties of thermally reduced graphene\ud oxide (rGO) layers, from room temperature to 2 K and in presence of magnetic fields up to\ud 7 T. The most conductive rGO sheets follow different transport regimes: at room temperature\ud they show an Arrhenius-like behavior. At lower temperature they exhibits a thermally\ud activated behavior with resistance R following a R = R0exp(T0/T)p law with p = 1/3, consistently\ud with 2D Mott Variable Range Hopping (VRH) transport mechanism. Below a given\ud temperature Tc, we observe a crossover from VHR to another regime, probably due to a\ud shortening of the characteristic lengths of the disordered 2D system. The temperature Tc\ud depends on the reduction grade of the rGO. Magnetoresistance DR/R of our rGO films shows\ud as well a crossover between positive and negative and below liquid He temperature DR/R\ud reaches values larger than 60%, surprisingly high for a – nominally – non magnetic\ud material