Quantum emitters coupled to surface plasmons of a nano-wire: A Green function approach

TL;DR

This paper models and analyzes how quantum emitters interact with surface plasmons on a nano-wire, revealing phenomena like superradiance and proposing applications in quantum gates and many-body physics.

Contribution

It introduces a Green function approach to quantify emitter-plasmon interactions, including decay rates and atom-atom couplings, and explores potential quantum information applications.

Findings

Observation of Dicke superradiance and subradiance mediated by plasmons

Derivation of explicit formulas for decay rates and couplings

Proposal of a scheme for a deterministic two-qubit quantum gate

Abstract

We investigate a system consisting of a single, as well as two emitters strongly coupled to surface plasmon modes of a nano-wire using a Green function approach. Explicit expressions are derived for the spontaneous decay rate into the plasmon modes and for the atom-plasmon coupling as well as a plasmon-mediated atom-atom coupling. Phenomena due to the presence of losses in the metal are discussed. In case of two atoms, we observe Dicke sub- and superradiance resulting from their plasmon-mediated interaction. Based on this phenomenon, we propose a scheme for a deterministic two-qubit quantum gate. We also discuss a possible realization of interesting many-body Hamiltonians, such as the spin-boson model, using strong emitter-plasmon coupling.