# Anisotropy and controllable band structure in supra-wavelength polaritonic metasurfaces

## TL;DR

This paper demonstrates how to create and control anisotropic, supra-wavelength polaritonic metasurfaces using organic dye stripes on silver, revealing tunable band structures and unidimensional polaritons through simulation and experiments.

## Contribution

It introduces a method to engineer anisotropic metasurfaces with controllable band structures using extended coherence of plasmon/exciton states.

## Key findings

- Effective metasurface behavior observed at periods much larger than wavelength
- Anisotropy and modified band structures successfully simulated and measured
- Unidimensional polaritons demonstrated in experiments

## Abstract

In this letter we exploit the extended coherence length of mixed plasmon/exciton states to generate active metasurfaces. For this purpose, periodic stripes of organic dye are deposited on a continuous silver film. Typical metasurface effects, such as effective behavior and geometry sensitivity, are measured for periods exceeding the polaritonic wavelength by more than one order of magnitude. By adjusting the metasurface geometry, anisotropy, modified band structure and unidimensional polaritons are computationally simulated and experimentally observed in reflectometry as well as in emission.