Abstract

We demonstrate a spectroscopy technique that uses nuclear spins as a non-invasive probe of few-electron states in optically active GaAs quantum dots. Experiments on low-strain GaAs/AlGaAs epitaxial dots reveal energy spectra for charge configurations with up to seven electrons, including shell filling, ground-state phase transitions, strong spin-orbit coupling, and anomalously fast nuclear spin diffusion. The measurements are supported by first-principles configuration-interaction numerical modelling.

Abstract

We demonstrate a spectroscopy technique that uses nuclear spins as a non-invasive probe of few-electron states in optically active GaAs quantum dots. Experiments on low-strain GaAs/AlGaAs epitaxial dots reveal energy spectra for charge configurations with up to seven electrons, including shell filling, ground-state phase transitions, strong spin-orbit coupling, and anomalously fast nuclear spin diffusion. The measurements are supported by first-principles configuration-interaction numerical modelling.

Abstract

We demonstrate a spectroscopy technique that uses nuclear spins as a non-invasive probe of few-electron states in optically active GaAs quantum dots. Experiments on low-strain GaAs/AlGaAs epitaxial dots reveal energy spectra for charge configurations with up to seven electrons, including shell filling, ground-state phase transitions, strong spin-orbit coupling, and anomalously fast nuclear spin diffusion. The measurements are supported by first-principles configuration-interaction numerical modelling.

Abstract

We demonstrate a spectroscopy technique that uses nuclear spins as a non-invasive probe of few-electron states in optically active GaAs quantum dots. Experiments on low-strain GaAs/AlGaAs epitaxial dots reveal energy spectra for charge configurations with up to seven electrons, including shell filling, ground-state phase transitions, strong spin-orbit coupling, and anomalously fast nuclear spin diffusion. The measurements are supported by first-principles configuration-interaction numerical modelling.