Dependence of Rabi-splitting on the spatial position of the optically active layer in organic microcavities in the strong coupling regime

Optical organic "semiconductor" microcavities exhibiting strong coupling were prepared. Thin layers of the dye 1, 1′-diethyl-2,2′-cyanine (PIC), which is known to form J-aggregates, were used as the optically active material. Spin coating of a specific dye salt made it possible to prepare thin J-aggregate layers within a λ/2-cavity without the need of any polymer-matrix. SiOx buffer layers were used to place the optically active J-aggregate layer at different positions inside the cavity. Transmission measurements revealed different vacuum Rabi-splitting energies between 26 and 52 meV. A dipole approximation was used to explain the dependence of the vacuum Rabi-splitting energy on the spatial position inside the cavity. © 2002 Elsevier Science B.V. All rights reserved.