Tunable narrowband Excitonic Optical Tamm States enabled by a metal-free all-organic structure

TL;DR

This paper introduces a novel, fully organic, metal-free structure supporting tunable optical Tamm states using polymeric materials, enabling lightweight, flexible, and cost-effective excitonic devices with narrowband optical confinement.

Contribution

It demonstrates the first all-organic, metal-free structure supporting optical Tamm states, with tunability achieved through multilayer periodicity variation.

Findings

Successful fabrication of large-area organic OTS structures

Tunable narrowband optical confinement achieved

Potential for lightweight, flexible excitonic devices

Abstract

Optical Tamm States (OTS) are confined optical modes that can occur at the interface between two highly reflective structures. However, due to the strong reflectance required, their implemen-tation with highly processable and metal-free flexible materials has proven challenging. Herein, we develop the first structure supporting OTS based only on organic polymeric materials, demon-strating a photonic platform based on non-critical, widely available, and easily processable mate-rials. The structures fabricated present large areas and consist of a narrowband multi-layered polymeric Distributed Bragg Reflector (DBR) followed by a thin film of J-aggregate molecular exci-tonic material that can act as a highly reflective surface within a narrowband range. We take ad-vantage of the narrowband spectral response of the DBR and of the reflective molecular layer to tune the OTS band by varying the periodicity of the multilayer, opening the door for the fabrica-tion of OTS structures based on lightweight integrable excitonic devices with cost-effective proce-dures.