Routing surface plasmons by a quantum-dot nanostructure: nonlinear dispersion effects

TL;DR

This paper explores how nonlinear dispersion influences quantum routing of surface plasmons in a double quantum-dot setup, revealing enhanced routing capabilities and Fano-like resonances, advancing quantum plasmonic network control.

Contribution

It demonstrates that nonlinear dispersion in a double quantum-dot system significantly improves surface plasmon routing and introduces controllable Fano-like resonances.

Findings

Routing probabilities are enhanced by nonlinear dispersion.

Quadratic dispersion leads to Fano-like resonances.

Designing inter-dot distance and coupling improves routing efficiency.

Abstract

Usually, the liner waveguides with single quantum emitters are utilized as routers to construct the quantum network in quantum information processings. Here, we investigate the influence of the nonlinear dispersion on quantum routing of single surface plasmons, between two metal nanowires with a pair of quantum dots. By using a full quantum theory in real space, we obtain the routing probabilities of a single surface plasmon into the four outports of two plasmonic waveguides scattered by a pair of quantum dots. It is shown that, by properly designing the inter-dot distance and the dot-plasmon couplings, the routing capability of the surface plasmons between the plasmonic waveguide channels can be significantly higher than the relevant network formed by the single-emitter waveguides with the linear dispersions. Interestingly, the present quadratic dispersions in the waveguides deliver the manifest Fano-like resonances of the surface-plasmon transport. Therefore, the proposed double-dot configuration could be utilized as a robust quantum router for controlling the surface-plasmon routing in the plasmonic waveguides and a plasmonic Fano-like resonance controller.