Macroscopic coherence of a single exciton state in a polydiacetylene organic quantum wire

TL;DR

This paper demonstrates that a single exciton in a conjugated polymer chain exhibits macroscopic quantum coherence over tens of microns, confirmed through interference of separated emission regions.

Contribution

It provides experimental evidence of macroscopic quantum coherence in a single exciton state within an organic quantum wire, a novel observation in conjugated polymers.

Findings

Exciton coherence extends over tens of microns.

Interference observed between spatially separated emission regions.

Coherence limited by the chain length.

Abstract

We show that a single exciton state in an individual ordered conjugated polymer chain exhibits macroscopic quantum spatial coherence reaching tens of microns, limited by the chain length. The spatial coherence of the k=0 exciton state is demonstrated by selecting two spatially separated emitting regions of the chain and observing their interference.