Cavity Polaritons in a Single-Crystalline Organic Microcavity Prepared at Room Temperature Using a Simple Solution Technique

Abstract

We have developed a novel method of fabricating high-quality crystalline organic microcavities using a simple solution technique. Anthracene single crystals were grown from solution at room temperature in a gap of 200 nm between two joined distributed Bragg reflectors. The method is easier to perform than the conventional melting technique and the crystals have no strain caused by thermal expansion. Clear cavity polariton modes and giant Rabi splitting energies were observed as well as those in the microcavities prepared using the melting technique. The method can be applied to the fabrication of various crystalline organic microcavities. #

Light–Matter Coupling Strength Controlled by the Orientation of Organic Crystals in Plasmonic Cavities

“…We use single-crystalline tetracene as excitonic material. Tetracene is an extensively studied organic crystal because of the efficient singlet fission and its potential to enhance solar cell quantum efficiency up to 200%. − Light–matter coupling has been studied before in tetracene and TIPS-tetracene, showing coupling with both excitons in multicrystalline , and single-crystal tetracene. , Also other organic crystals with strongly oriented dipole moments have been studied. − However, these measurements were performed in FP cavities with an isotropic in-plane cavity field, while we study the coupling to an anisotropic cavity of silver nanoparticles, allowing the investigation of the onset of strong coupling.…”

Anticrossing Behavior in Nanolayered Heterostructures Caused by Coupling between a Planar Waveguide Mode in an Anthracene Single Crystal and a Silver Surface Plasmon Polariton Mode: Implications for Attenuated Total Reflection Spectroscopy

“…The presence of single crystals with planes parallel to the surfaces of the substrates, which were the abplanes of the crystals, was verified through observation with a polarizing microscope. 36 The in-plane dimensions of a number of crystals were confirmed as several hundred micrometers. The crystal in the center of the micrograph, as shown in Figure 1b, is the focus of the present work.…”

“…Therefore, large oscillator strength is concentrated in specific crystal orientations, and the plasmon effect is thought to be prominent in these orientations. In fact, in the study of cavity polaritons, there are several reports of organic single crystals. − Large optical anisotropy and large Rabi splitting energies exceeding 300 meV have been observed in the anthracene single-crystalline cavity polaritons. The splitting energies are quite large among organic materials, including disordered materials.…”

“…Ag thin films were deposited on the two quartz substrates via a vacuum evaporation technique. The Ag mirrors were sandwiched between two aluminum plates and fixed with screws, and an empty Fabry–Pérot (FP) microcavity was fabricated. − The width of the gap between the Ag mirrors was adjusted using screws and was estimated by comparing the measured transmission spectra of the cavity with calculations based on the transfer matrix theory, which is discussed in more detail later in this paper. Finally, the width was set to hundreds of nanometers by repeating these processes.…”

“…Anthracene single crystals were grown in the cavity using a solution growth technique at room temperature (RT). , Following crystal growth, the screws were loosened slightly and the cavity length was extended by hundreds of nanometers, which caused air gaps to form between the anthracene crystals and either Ag mirror, as depicted in Figure a. The air gap width was estimated from the transmission spectra and calculations based on the transfer matrix theory.…”