# Contamination of polymethylmethacrylate by organic quantum emitters

## TL;DR

This study reveals widespread organic molecule contamination in polymethylmethacrylate, creating fluorescence hot-spots with high quantum yields, and suggests a simple method for developing visible-range single-photon sources.

## Contribution

It uncovers the contamination of PMMA by organic fluorophores and demonstrates their potential for cost-effective single-photon source applications.

## Key findings

- Contamination sites act as fluorescence hot-spots.
- Quantum yields approach 30% at cryogenic temperatures.
- Findings clarify spectral features in polymer nanoemitters.

## Abstract

We report the observation of ubiquitous contamination of polymethylmethacrylate by organic molecules with optical activity in the visible spectral range. Contamination sites of individual solvent-specific fluorophores in thin films of polymethylmethacrylate constitute fluorescence hot-spots with quantum emission statistics and quantum yields approaching 30% at cryogenic temperatures. Our findings not only resolve prevalent puzzles in the assignment of spectral features to various nanoemitters in polymer matrices, they also identify means for simple and cost-efficient realization of single-photon sources in the visible spectral range.