Optical coupling of Frenkel excitons in organic semiconductor microcavities

Planar microcavity structures provide a versatile means to control the opti cal properties of semiconductors. In this paper, we describe strongly-coupl ed microcavities that contain two different organic dyes that are separated by a 100 mn thickness spacer layer. We show that simultaneous strong coupl ing of the individual Frenkel exciton species to a single cavity photon mod e leads to new eigenmodes that can be described as admixtures of all three states. These new 'hybrid' exciton-photon structures are of potential inter est as systems to study coherent coupling between Frenkel excitons. They fu rther demonstrate the sophisticated control over light-matter coupling achi evable using microcavities. (C) 2001 Elsevier Science B.V. All rights reser ved.