Room temperature single-photon superfluorescence from a single epitaxial cuboid nano-heterostructure

TL;DR

This paper demonstrates room temperature single-photon superfluorescence from a specially designed nanocuboid, showcasing collective emission phenomena in a nanomaterial system that was previously only observed at cryogenic temperatures.

Contribution

The authors design and synthesize a nanocuboid that hosts nearly identical emitters capable of exhibiting superradiance at room temperature, a feat not achieved in prior nanomaterials.

Findings

Room temperature superfluorescence observed in single nanocuboids.

Superradiant and subradiant states detected at room temperature.

Nanocuboid design enables robust collective emission phenomena.

Abstract

Single-photon superradiance can emerge when a collection of identical emitters are spatially separated by distances much less than the wavelength of the light they emit, and is characterized by the formation of a superradiant state that spontaneously emits light with a rate that scales linearly with the number of emitters. This collective phenomena has only been demonstrated in a few nanomaterial systems, all requiring temperatures below 10K. Here, we rationally design a single colloidal nanomaterial that hosts multiple (nearly) identical emitters that are impervious to the fluctuations which typically inhibit room temperature superradiance in other systems such as molecular aggregates. Specifically, by combining molecular dynamics, atomistic electronic structure calculations, and model Hamiltonian methods, we show that the faces of a heterostructure nanocuboid mimic individual quasi-2D nanoplatelets and can serve as the robust emitters required to realize superradiant phenomena at room temperature. Leveraging layer-by-layer colloidal growth techniques to synthesize a nanocuboid, we demonstrate single-photon superfluorescence via single-particle time-resolved photoluminescence measurements at room temperature. This robust observation of both superradiant and subradiant states in single nanocuboids opens the door to ultrafast single-photon emitters and provides an avenue to entangled multi-photon states via superradiant cascades.