Charge Carriers in Organic Electronics: Solitons and Polarons

This lecture covers the formation and delocalization of charge carriers in organic materials, focusing on solitons and polarons. It begins with an introduction to organic electronics, highlighting the historical context and challenges faced in the field. The instructor explains the concept of intramolecular electron delocalization, detailing the transition from atomic to molecular orbitals, particularly in π-conjugated systems. The discussion progresses to the nature of solitons, unique charge carriers in polyacetylene, and their role in charge transport. The lecture also addresses polarons, their formation, and the impact of chemical doping on conductivity. The instructor emphasizes the differences between neutral solitons and charged species, illustrating how doping alters the electronic properties of materials. The effects of dynamic and static disorder on charge transport mechanisms are explored, with a focus on the implications for device performance. The lecture concludes with insights into the behavior of charge carriers at interfaces and the importance of understanding these concepts for advancing organic semiconductor technology.