Review and Perspectives of Micro/Nano Technologies as Key-Enablers of 6G

To date, the rollout of 5G (5th generation of mobile communications) has been ongoing for more than two years, with most of it still to come. Meanwhile, Key-Performance Indicators (KPIs) and Key Enabling Technologies (KETs) of Beyond-5G (B5G) and 6G (6th generation of mobile communications) are already at stake, looking toward 2030. Future networks will leverage autonomous and evolutionary characteristics, triggered by the cornerstone of Artificial Intelligence (AI), falling well beyond the scope of 5G. Further, a seamless increase of KPIs, across the transition from 5G to 6G, with 100-1000 times higher data rate per user, latency reduction and reliability improvement, also stepping into the domain of (sub-)THz and optical communications, will set unparalleled demands for Hardware (HW) systems and components. This work focuses on the envisaged gap existing between currently in-use strategies for design of Hardware-Software (HW-SW) systems and what the AI-driven 6G will demand, in terms of adaptivity, flexibility and evolution. An important aspect is a forecast for Micro/Nano technologies, devices and systems, in enabling 6G functionalities, especially at the network edge, stimulating partial reconceptualization of the classical idea of HW, in fact, rising its level of abstraction.