Charge transfer at organic semiconductor hetero-interfaces: Towards a unified picture in intermediate cases of ground state and excited state scenarios

In this proposal, we study the charge transfer at organic semiconductor hetero-interfaces using the joint expertise of three groups. Our aim is to obtain a comprehensive understanding of the electronic processes and optical properties involved by combining complementary experimental techniques, including growth and structural studies, electrical transport investigations, optical spectroscopy and analysis of the electronic structure. Interaction between the involved molecules appear both in the ground state and after optical excitation. Suitable material combinations allowing for charge transfer across their mutual interfaces will be identified and the electronic properties of the resulting organic semiconductor heterostructures will be studied. The focus is on the degree of charge transfer, the binding energy and the anisotropy of the charge transfer state, as well as the shape of density of states.