Quantum Light from a Metal Nanoparticle

TL;DR

This paper reveals that a metal nanoparticle can act as a quantum emitter, producing high-rate, antibunched single photons, which could revolutionize single-photon source technology.

Contribution

It demonstrates that metal nanoparticles can serve as quantum emitters, enabling ultra-fast single-photon generation beyond traditional emitter limitations.

Findings

Metal nanoparticles can behave as quantum emitters.

The emitted light shows sub-Poissonian statistics and antibunching.

Potential for single-photon sources with rates up to 100 THz.

Abstract

Single-photon sources are subjected to a fundamental limitation in the speed of operation dictated by the spontaneous emission rate of quantum emitters (QEs). The current paradigm of the rate acceleration suggests coupling of a QE to a metal nanostructure, in particular, a metal nanoparticle (MNP). Here, we demonstrate that, in contrast to this approach, a MNP itself can behave as a quantum emitter. We determine both the first- and second-order correlation functions of light spontaneously emitted by a MNP strongly coupled to a QE and show that this light should exhibit sub-Poissonian photon statistics and perfect photon antibunching. This discovery opens a prospect to single-photon sources with unprecedented generation rates up to 100 THz.