Entangled two-plasmon generation in carbon nanotubes and graphene coated wires

TL;DR

This paper explores the efficient generation of entangled two-plasmon states near carbon nanotubes and graphene-coated wires, revealing significantly enhanced emission rates and tunable spectra, with potential applications in quantum information processing.

Contribution

It demonstrates the strong coupling and high emission rates of two-plasmon states in low-dimensional carbon nanostructures, and shows how to tailor their properties for quantum technologies.

Findings

Two-plasmon emission rates over twelve orders higher than free-space.

Tunable emission spectra with sharp resonances at plasmon excitation frequencies.

Material property modifications allow control over emission modes and frequencies.

Abstract

We investigate the two-plasmon spontaneous decay of a quantum emitter near single-walled carbon nanotubes (SWCNT) and graphene-coated wires (GCWs). We demonstrate efficient, enhanced generation of two-plasmon entangled states in SWCNTs due to the strong coupling between tunable guided plasmons and the quantum emitter. We predict two-plasmon emission rates more than twelve orders of magnitude higher than in free-space, with average lifetimes of a few dozens of nanoseconds. Given their low dimensionality, these systems could be more efficient for generating and detecting entangled plasmons in comparison to extended graphene. Indeed, we achieve tunable spectrum of emission in GCWs, where sharp resonances occur precisely at the plasmons' minimum excitation frequencies. We show that, by changing the material properties of the GCW's dielectric core, one could tailor the dominant modes and frequencies of the emitted entangled plasmons while keeping the decay rate ten orders of magnitude higher than in free-space. By unveiling the unique properties of two-plasmon spontaneous emission processes in the presence of low dimensional carbon-based nanomaterials, our findings set the basis for a novel material platform with applications to on-chip quantum information technologies.