Confinement-induced versus correlation-induced electron localization and wave function entanglement in semiconductor nano dumbbells

Single-particle plus many-particle calculations of the electronic states of semiconductor nano dumbbells show how geometrical features (e.g., the width of the dumbbell wire) determine, through quantum confinement and electron-electron correlation effects, the spatial localization and the degree of entanglement of the electronic wave functions. Remarkably, we find that correlation effects can alter carrier localization and that the degree of wave function entanglement can be tuned by changing the diameter of the dumbbell wire. We further show how the exciton binding energy depends on the nano dumbbell geometry.