Diamond/graphene (carbon sp3-sp2) heterojunctions for neuromorphic device applications

Diamond/graphene (carbon sp 3 -sp 2 ) interfaces exhibit various interesting and potentially useful electronic phenomena. The present work demonstrates the possibility of obtaining novel neuromorphic photodevices using such junctions. Junctions were found to show different photoconductivity relaxation behavior depending on their growth conditions such that various optoelectronic properties were observed. In particular, interfaces exhibiting shorter relaxation times could be used to construct image recognition devices mimicking short-term memory functions of the human brain. Using these devices, images of the hand-written numerals 0 through 9 could be optoelectronically recognized with an accuracy on the order of 80%, demonstrating both photo-detection and processing functions in a single device. These results suggest that novel image processing devices could be produced using graphene/diamond heterojunctions. Graphical Abstract