Magneto-tunnelling spectroscopy of single self-assembled InAs quantum dots in AlAs

Abstract

We observe the spin splitting of a single InAs quantum dot using magneto-tunnelling spectroscopy. The current–voltage characteristics at low temperature are dominated by a Fermi edge singularity, caused by electron interaction effects. We obtain a value for the g-factor (=0.82±0.09) for the quantum dot, with magnetic field applied in the plane of the dot. The magnetic field dependence of the amplitude of the tunnel current provides us with an estimate of the size of the quantum dot wave function (9 nm).