Emission spectrum of a dressed exciton-biexciton complex in a semiconductor quantum dot

TL;DR

This study investigates the emission spectrum of a single quantum dot under resonant laser dressing, revealing fine-structure splittings sensitive to laser parameters, and demonstrates control over multi-excitonic emission.

Contribution

It provides the first detailed polarization-resolved spectral analysis of dressed exciton-biexciton states in quantum dots with tunable splittings.

Findings

Splittings depend on laser intensity and detuning.

Splittings manifest as triplets or doublets.

Complete resonant control of multi-excitonic emission achieved.

Abstract

The photoluminescence spectrum of a single quantum dot was recorded as a secondary resonant laser optically dressed either the vacuum-to-exciton or the exciton-to-biexciton transitions. High-resolution polarization-resolved measurements using a scanning Fabry-Perot interferometer reveal splittings of the linearly-polarized fine-structure states that are non-degenerate in an asymmetric quantum dot. These splittings manifest as either triplets or doublets and depend sensitively on laser intensity and detuning. Our approach realizes complete resonant control of a multi-excitonic system in emission, which can be either pulsed or continuous-wave, and offers direct access to the emitted photons.