Magneto-tunnelling spectroscopy for spatial mapping of orbital wavefunctions of the ground and excited electronic states in self-assembled quantum dots

We present an experimental study of electron wavefunctions in InAs/GaAs sel f-assembled quantum dots (QDs). Magneto-tunnelling spectroscopy is employed as a nan-invasive probe to produce two-dimensional images of the probabili ty density of an electron confined in a quantum dot. The images reveal clea rly the elliptical symmetry of the ground state and the characteristic lobe s of the higher energy states of the dots. We use the technique to compare the symmetry properties of the electron wavefunctions in QDs grown on (100) - and (311)B-oriented GaAs substrates.