PHOTOCODE · Photodriven spin selectivity in chiral organic molecules and devices

The control of electron spin with light in organic semiconductors holds great potential to revolutionise several organic electronic industries such as renewable energy, illumination and displays, informatics, sensing and healthcare. However, beneath the glamour and excitement of these promises lies the stark reality. In fact, the intrinsic carbon-based nature of organic materials engenders low spin-orbit coupling, thereby hindering efficient electron spin manipulation mediated by light. In this context, the chiral induced spin selectivity (CISS) effect has paved the way for a new paradigm to provide spin control at molecular level through the chirality of organic molecules. Despite being very promising, the lack of direct experimental evidence, and thus in-depth understanding of the CISS effect has prevented it from unleashing its full potential for technological and commercial applications.The PHOTOCODE project aims to extend the concept of the CISS effect from the field of spintronics to organic optoelectronics and to achieve unprecedented control of the electron spin in organic molecules and devices. The scientific idea behind this ambitious aim consists of getting access to the photoexcited spin interactions in novel chiral donor-bridge-acceptor organic dyads via sophisticated optical and spin-sensitive techniques. Following an interdisciplinary approach based on advanced photophysical characterization and molecular engineering, backed by quantum mechanical calculations, PHOTOCODE will ultimately enable the fabrication of spin photovoltaic devices, where spin currents are generated following light absorption and charge transfer. In a broader sense, PHOTOCODE will not only foster a better understanding of spin processes in organic semiconductors but also extend the reach of organic materials to the exciting field of organic opto/spintronics.