# Anomalous dispersion in coupled surface plasmons and excitons

## TL;DR

This paper explores unusual light behavior in polymer materials mixed with dyes, revealing new patterns in how light and matter interact.

## Contribution

The study introduces new dispersion phenomena in dye-polymer systems, including multi-branch and fork-like dispersion curves.

## Key findings

- Multi-branch 'staircase' dispersion curves were observed in singly and doubly doped PMMA polymer.
- A new 'fork' dispersion branch emerged in the system.
- High dye concentration enabled strong coupling without the need for metal.

## Abstract

We studied dispersion in Rhodamine laser dyes in the Kretschmann geometry and found (i) multi-branch “staircase” dispersion curves in singly doped and double doped PMMA polymer, (ii) emergence of the new dispersion “fork” branch, (iii) unparallel dispersion and coupling in the mixture of two different dyes, and (iv) effect of high dye concentration on strong coupling without metal.