Controlling quantum-dot light absorption and emission by a surface-plasmon field

TL;DR

This paper investigates how a surface-plasmon field can control optical gain, absorption, and photon interactions in a quantum dot system, revealing nonlinear effects and potential applications in optical communication and quantum computing.

Contribution

It demonstrates the nonlinear control of quantum-dot optical properties via surface-plasmon fields, including induced gain and spectral splitting, advancing the understanding of photon-photon interactions in such systems.

Findings

Observation of induced optical gain in quantum dots

Spectral splitting of spontaneous emission peaks

Potential for ultrafast optical switching applications

Abstract

The possibility for controlling the probe-field optical gain and absorption switching and photon conversion by a surface-plasmon-polariton near field is explored for a quantum dot above the surface of a metal. In contrast to the linear response in the weak-coupling regime, the calculated spectra show an induced optical gain and a triply-split spontaneous emission peak resulting from the interference between the surface-plasmon field and the probe or self-emitted light field in such a strongly-coupled nonlinear system. Our result on the control of the mediated photon-photon interaction, very similar to the `gate' control in an optical transistor, may be experimentally observable and applied to ultra-fast intrachip/interchip optical interconnects, improvement in the performance of fiber-optic communication networks and developments of optical digital computers and quantum communications.