Dark exciton states in a single semiconductor quantum dot

Semiconductor quantum dots (QDs) are a promising system to produce non-classical states of light that will be used in a variety of emerging quantum technologies [1]. Bright non-classical light is often made by the coupling of a single excitonic quasi-particle from a single QD with in-situ micrometre-scale optical cavities using mainstream semiconductor fabrication. While counterintuitive, the investigation of exciton states that do not interact with optical fields is also important as these states can serve as long-lived ground states.

After an introduction to the QD exciton system, micrometre-scale optical cavities, and the interaction of optical fields and with discreet states, I will discuss a recent set of experiments with dark exciton states. We measure properties of these dark exciton states and show how they are linked to other states in the QD.

[1] P. Senellart, G. Solomon, and A. White, “High-performance semiconductor quantum-dot single-photon sources,” Nature Nanotechnology 12, 1026 (2017).