Graphene nanoRibbons as Atomically controlled Light Sources – Graal

Since their first on-surface synthesis, atomically precise graphene nanoribbons (GNRs) have attracted tremendous interest in the nano-science and technology communities. Their optical properties in particular hold great promise towards robust and controllable atomically thin classical and quantum emitters and for the realization of robust low-dimensional optoelectronic devices. In fact, GNRs combine many of the outstanding characteristics of graphene with an electronic gap, a mandatory property for many applications including light-emitting devices. Whereas theoretical studies discuss in great detail how the optical properties of GNRs may be advantageously controlled through atomic-scale variations of their width, length, and edge shapes, experiments reporting on the excitonic properties of GNRs are scarce, especially those focusing on photon emission. Indeed, because the synthesis of these GNRs is performed directly on metallic surfaces – which in turn causes luminescence quenching – the light emission properties (being classical or quantum) of atomically precise GNRs remain almost unexplored territory. This synthesis method constitutes also a difficulty when it comes to the realization of GNRs-based optoelectronic devices, as efficient strategies to transfer the GNRs are still lacking.
To tackle these issues we propose (i) to exploit an unconventional decoupling strategy that we developed recently (arXiv:2209.01471 – French partner) based on LT-STM experiments to unravel the atomic-scale classic and quantum emission properties of individual GNRs and (ii) to integrate the most relevant GNRs in photonic and optoelectronic devices thanks to an innovative solution (Swiss partner) aiming at protecting the optical properties of the GNRs by using dry transfer methods.
An interdisciplinary consortium composed of internationally recognized surface chemists and physicists from Switzerland (EMPA) and France (IPCMS) is built to address these issues.