Determinstic Generation of a Quantum Dot-Confined Triexciton and its Radiative Decay via Three-Photon Cascade

TL;DR

This paper demonstrates the deterministic generation of a quantum dot-confined triexciton and its three-photon radiative decay cascade, advancing quantum photon source development for quantum information processing.

Contribution

It introduces a method for deterministic triexciton generation and directly measures the three-photon cascade, a novel step beyond biexciton-based photon sources.

Findings

Successful deterministic triexciton generation in a quantum dot.

Spectral identification of the three-photon cascade.

Direct measurement of the sequential radiative decay.

Abstract

Semiconductor quantum dots (QDs) have potential applications in quantum information processing due to the fact that they are potential on-demand sources of single and entangled photons. Generation of polarization-entangled photon pairs was demonstrated using the biexciton-exciton radiative cascade. One obvious way to increase the number of quantum correlated photons that the QDs emit is to use higher-order multiexcitons, in particular the triexciton. Towards achieving this goal, we first demonstrate deterministic generation of the QD-confined triexciton in a well-definedcoherent state and then spectrally identify and directly measure a three-photon radiative cascade resulting from the sequential triexciton-biexciton-exciton radiative recombination.