Spin pairs in a weakly coupled many-electron quantum dot

TL;DR

This study observes numerous consecutive spin pairs in a weakly coupled many-electron quantum dot, using Coulomb resonance shifts and charge detection to analyze tunneling rates and compare with theoretical models.

Contribution

It reports the first observation of many consecutive spin pairs in a weakly coupled many-electron quantum dot and analyzes their tunneling behavior.

Findings

Numerous consecutive spin pairs observed in the quantum dot.

Tunneling rates depend on gate voltage and magnetic field.

Comparison with a single-level transport model reveals deviations.

Abstract

We report the observation of an unusually large number of consecutive spin pairs in a weakly coupled many-electron GaAs/AlGaAs quantum dot. The pairs are identified due to pairwise parallel shifts of Coulomb resonances in a perpendicular magnetic field. Using a nearby quantum point contact for time-resolved charge detection, the tunneling rates are investigated as a function of gate voltage and magnetic field. We compare our experimental data to a single-level transport model and discuss possible reasons for deviations.