# Controlling Single-Emitter Strong Coupling by Sculpting DNA Dye Scaffolds in NPoM Cavities

## TL;DR

This paper shows how DNA scaffolds can control the coupling of light and single molecules in nanocavities, enabling tunable light emission.

## Contribution

The study introduces a method to tune plasmonic modes using DNA origami scaffolds for consistent strong coupling with single emitters.

## Key findings

- DNA scaffold design affects how dye molecules couple to nanocavity optical fields.
- Strong coupling consistently results in low-energy light emission regardless of detuning.
- Au atoms respond to optical forces based on DNA architecture, enabling plasmonic mode tuning.

## Abstract

Coherent coupling
of light and single molecules enables the development
of next-generation room temperature-capable nanophotonic devices.
Small mode-volume optical fields can be achieved with plasmonics,
but challenges remain in placing oriented emitter molecules inside
plasmonic cavities to access strong coupling consistently in emission.
Using DNA origami, single-emitter molecules can be aligned inside
subnanometric cavities created between a gold nanoparticle and a gold
mirror. We observe that the exact design of DNA scaffolding architecture
surrounding a cyanine dye changes how its emission couples to the
nanocavity, as well as how Au atoms respond to the optical forces,
leading to continuous tuning of the dominant plasmonic mode. Through
this, we show how strong coupling between three different dyes and
the plasmon resonance always leads to low-energy light emission, independent
of detuning.