Coulomb-assisted cavity feeding in the non-resonant optical emission from a quantum dot

TL;DR

This paper investigates how Coulomb-mediated Auger processes enable off-resonant cavity emission from quantum dots, revealing efficient coupling at high carrier densities through a novel non-perturbative theoretical approach.

Contribution

It introduces a new theoretical method to analyze Coulomb-assisted cavity feeding, demonstrating its effectiveness in off-resonant emission at high carrier densities.

Findings

Coulomb-mediated Auger processes facilitate off-resonant emission.

Efficient cavity feeding occurs at higher carrier densities.

Reduced efficiency compared to intraband scattering processes.

Abstract

Recent experiments have demonstrated that for a quantum dot in an optical resonator off-resonant cavity mode emission can occur even for detunings of the order of 10 meV. We show that Coulomb mediated Auger processes based on additional carriers in delocalized states can facilitate this far off-resonant emission. Using a novel theoretical approach for a non-perturbative treatment of the Auger-assisted quantum-dot carrier recombination, we present numerical calculations of the far off-resonant cavity feeding rate and cavity mean photon number confirming efficient coupling at higher densities of carriers in the delocalized states. In comparison to fast Auger-like intraband scattering processes, we find a reduced overall efficiency of Coulomb-mediated interband transitions due the required electron-hole correlations for the recombination processes.