Reshaping 2D semiconducting layers for large-scale photon harvesting and nanoelectronics.

Two-dimensional (2D) Transition Metal Dichalcogenide semiconductors (TMDs) have attracted diffuse interest due to their exceptional optoelectronic properties. However, the inherent low photon absorption of the atomic layers demands novel light coupling schemes. Additionally, there is an urgent request to scale up the lateral size of the 2D layers, limited in micrometric flakes, and to engineer their shape at the nanoscale. Here the nanoscale reshaping of 2D TMDs layers is shown over large-scale demonstrating superior photon harvesting properties, and opening new perspectives in nanoelectronics. In a first activity we show a flat-optics scheme based on large-area few-layers $MoS_{2}$ forming periodic nanogratings. These 2D nanopatterned layers support Rayleigh anomalies that promote strong in-plane light confinement and photon absorption enhancement, with impact in photo-conversion. As a step forward, arbitrarily defined few-layer $MoS_{2}$ nanopaths has been achieved thanks to a new additive nanofabrication, based on the thermal-Scanning Probe Lithography, showing the potential of these nanocircuits as building blocks for nanoelectronics and nanophotonics.