Tunable light-matter hybridization in open organic microcavities

Abstract

Open microcavities represent a versatile cavity design that allows the external control of internal properties such as cavity thickness and mode detuning without changing the key parameters of the cavity itself, rendering them particularly interesting for light-matter interaction experiments. Here, we demonstrate the tunability of an open microcavity with an embedded active organic layer providing parallel alignment of molecular transition dipole moments as well as strong self-absorption inside the cavity. By decreasing the cavity thickness, we observe a transition from the weak coupling regime into the strong coupling regime evidenced by the onset of avoided crossing behavior between involved modes. This change of coupling mechanism is shown for 2D (planar) as well as 0D (hemispherical) cavities.